The cytokine storm in COVID-19: An overview of the involvement of the chemokine/chemokine-receptor system

Sarbecovirus disease susceptibility is conserved across viral and host models

Coronaviruses have caused three severe epidemics since the start of the 21st century: SARS, MERS and COVID-19. The severity of the ongoing COVID-19 pandemic and increasing likelihood of future coronavirus outbreaks motivates greater understanding of factors leading to severe coronavirus disease. We screened ten strains from the Collaborative Cross mouse genetic reference panel and identified strains CC006/TauUnc (CC006) and CC044/Unc (CC044) as coronavirus-susceptible and resistant, respectively, as indicated by variable weight loss and lung congestion scores four days post-infection. We generated a genetic mapping population of 755 CC006xCC044 F2 mice and exposed the mice to one of three genetically distinct mouse-adapted coronaviruses: clade 1a SARS-CoV MA15 (n=391), clade 1b SARS-CoV-2 MA10 (n=274), and clade 2 HKU3-CoV MA (n=90). Quantitative trait loci (QTL) mapping in SARS-CoV MA15- and SARS-CoV-2 MA10-infected F2 mice identified genetic loci associated with disease severity. Specifically, we identified seven loci associated with variation in outcome following infection with either virus, including one, HrS43, that is present in both groups. Three of these QTL, including HrS43, were also associated with HKU3-CoV MA outcome. HrS43 overlaps with a QTL previously reported by our lab that is associated with SARS-CoV MA15 outcome in CC011xCC074 F2 mice and is also syntenic with a human chromosomal region associated with severe COVID-19 outcomes in humans GWAS. The results reported here provide: (a) additional support for the involvement of this locus in SARS-CoV MA15 infection, (b) the first conclusive evidence that this locus is associated with susceptibility across the Sarbecovirus subgenus, and (c) demonstration of the relevance of mouse models in the study of coronavirus disease susceptibility in humans.

Metabolomic Approach to Identify the Potential Metabolites from Alpinia malaccensis for Treating SARS-CoV-2 Infection

The advent of the new coronavirus, leading to the SARS-CoV-2 pandemic, has presented a substantial worldwide health hazard since its inception in the latter part of 2019. The severity of the current pandemic is exacerbated by the occurrence of re-infection or co-infection with SARS-CoV-2. Hence, comprehending the molecular process underlying the pathophysiology of sepsis and discerning possible molecular targets for therapeutic intervention holds significant importance. For the first time, 31 metabolites were tentatively identified by GC-MS analysis from Alpinia malaccensis. On the other hand, five phenolic compounds were identified and quantified from the plant in HPLC-DAD analysis, including (-) epicatechin, rutin hydrate, rosmarinic acid, quercetin, and kaempferol. Nine GC-MS and five HPLC-identified metabolites had shown interactions with 45 and 30 COVID-19-associated human proteins, respectively. Among the proteins, PARP1, FN1, PRKCA, EGFR, ALDH2, AKR1C3, AHR, and IKBKB have been found as potential therapeutic targets to mitigate SARS-CoV-2 infection. KEGG pathway analysis also showed a strong association of FN1, EGFR, and IKBKB genes with SARS-CoV-2 viral replication and cytokine overexpression due to viral infection. Protein-protein interaction (PPI) analysis also showed that TP53, MMP9, FN1, EGFR, and NOS2 proteins are highly related to the genes involved in COVID-19 comorbidity. These proteins showed interaction with the plant phytoconstituents as well. As the study offers a robust network-based procedure for identifying biomolecules relevant to COVID-19 disease, A. malaccensis could be a good source of effective therapeutic agents against COVID-19 and related viral diseases.

Upregulation of inflammatory genes and pathways links obesity to severe COVID-19

Obesity is a risk factor for developing severe COVID-19. However, the mechanism underlying obesity-accelerated COVID-19 remains unclear. Here, we report results from a study in which 2-3-month-old K18-hACE2 (K18) mice were fed a western high-fat diet (WD) or normal chow (NC) over 3 months before intranasal infection with a sublethal dose of SARS-CoV2 WA1 (a strain ancestral to the Wuhan variant). After infection, the WD-fed K18 mice lost significantly more body weight and had more severe lung inflammation than normal chow (NC)-fed mice. Bulk RNA-seq analysis of lungs and adipose tissue revealed a diverse landscape of various immune cells, inflammatory markers, and pathways upregulated in the infected WD-fed K18 mice when compared with the infected NC-fed control mice. The transcript levels of IL-6, an important marker of COVID-19 disease severity, were upregulated in the lung at 6-9 days post-infection in the WD-fed mice when compared to NC-fed mice. Transcriptome analysis of the lung and adipose tissue obtained from deceased COVID-19 patients found that the obese patients had an increase in the expression of genes and the activation of pathways associated with inflammation as compared to normal-weight patients (n = 2). The K18 mouse model and human COVID-19 patient data support a link between inflammation and an obesity-accelerated COVID-19 disease phenotype. These results also indicate that obesity-accelerated severe COVID-19 caused by SARS-CoV-2 WA1 infection in the K18 mouse model would be a suitable model for dissecting the cellular and molecular mechanisms underlying pathogenesis.

Ocular Manifestations of COVID-19

There is an increasing body of knowledge regarding how COVID-19 may be associated with ocular disease of varying severity and duration. This article discusses the literature on the ocular manifestations associated with COVID-19, including appraisal of the current evidence, suggested mechanisms of action, associated comorbidities and risk factors, timing from initial infection to diagnosis and clinical red flags. The current literature primarily comprises case reports and case series which inevitably lack control groups and evidence to support causality. However, these early data have prompted the development of larger population-based and laboratory studies that are emerging. As new data become available, a better appraisal of the true effects of COVID-19 on the eye will be possible. While the COVID-19 pandemic was officially declared no longer a "global health emergency" by the World Health Organization (WHO) in May 2023, case numbers continue to rise. Reinfection with different variants is predicted to lead to a growing cumulative burden of disease, particularly as more chronic, multi-organ sequelae become apparent with potentially significant ocular implications. COVID-19 ocular manifestations are postulated to be due to three main mechanisms: firstly, there is a dysregulated immune response to the initial infection linked to inflammatory eye disease; secondly, patients with COVID-19 have a greater tendency towards a hypercoagulable state, leading to prothrombotic events; thirdly, patients with severe COVID-19 requiring hospitalisation and are immunosuppressed due to administered corticosteroids or comorbidities such as diabetes mellitus are at an increased risk of secondary infections, including endophthalmitis and rhino-orbital-mucormycosis. Reported ophthalmic associations with COVID-19, therefore, include a range of conditions such as conjunctivitis, scleritis, uveitis, endogenous endophthalmitis, corneal graft rejection, retinal artery and vein occlusion, non-arteritic ischaemic optic neuropathy, glaucoma, neurological and orbital sequelae. With the need to consider telemedicine consultation in view of COVID-19's infectivity, understanding the range of ocular conditions that may present during or following infection is essential to ensure patients are appropriately triaged, with prompt in-person ocular examination for management of potentially sight-threatening and life-threatening diseases.

Post-COVID Trajectory of Pentraxin 3 Plasma Levels Over 6 Months and Their Association with the Risk of Developing Post-Acute Depression and Anxiety

BACKGROUND AND OBJECTIVES

Clinical manifestations of coronavirus disease 2019 (COVID-19) often persist after acute disease resolution. Underlying molecular mechanisms are unclear. The objective of this original article was to longitudinally measure plasma levels of markers of the innate immune response to investigate whether they associate with and predict post-COVID symptomatology.

METHODS

Adult patients with previous severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection during the first pandemic wave who underwent the 6-month multidisciplinary follow-up were included. Plasma levels of pentraxin 3 (PTX3), the complement components C3a and C5a, and chitinase-3 like-protein-1 (CHI3L1) were measured at hospital admission during acute disease (baseline) and at 1 and 6 months after hospital discharge. Associations with post-COVID-19 sequelae at 6 months were investigated using descriptive statistic and multiple regression models.

RESULTS

Ninety-four COVID-19 patients were included. Baseline PTX3, C5a, C3a, and CHI3L1 did not predict post-COVID-19 sequelae. The extent of the reduction of PTX3 over time (delta PTX3) was associated with lower depressive and anxiety symptoms at 6 months (both p < 0.05). When entering sex, age, need for intensive care unit or non-invasive ventilation during hospital stay, psychiatric history, and baseline PTX3 as nuisance covariates into a generalized linear model (GLM), the difference between baseline and 6-month PTX3 levels (delta PTX3) significantly predicted depression (χ2 = 4.66, p = 0.031) and anxiety (χ2 = 4.68, p = 0.031) at 6 months. No differences in PTX3 levels or PTX3 delta were found in patients with or without persistent or new-onset other COVID-19 symptoms or signs at 6 months. Plasma levels of C3a, C5a, and CHI3L1 did not correlate with PTX3 levels at either time point and failed to associate with residual or de novo respiratory or systemic clinical manifestations of the disease at 6 months.

CONCLUSIONS

A lower reduction of plasma PTX3 after acute COVID-19 associates with the presence of depression and anxiety, suggesting an involvement of inflammation in post-COVID-19 psychopathology and a potential role of PTX3 as a biomarker.

Cytokine storm modulation using cholecalciferol and low dose gamma radiation in Escherichia coli infected mice

This work investigates the efficiency of cholecalciferol and low dose gamma radiation in modulating cytokine storm through their impact on inflammatory and anti-inflammatory cytokine and protecting against lung and liver injuries. Male Swiss albino mice were exposed to 0.2 Gy gamma radiation/week for four consecutive weeks then injected intraperitoneally (i.p) with a single dose of 8.3 × 106 CFU Escherichia coli/g b.w. then injected i.p. with 1.0 mg/kg cholecalciferol (Vit D3) for 7 days starting 4 h after E. coli injection. The results revealed that Cholecalciferol and low dose gamma radiation caused significant depletion in the severity of E. coli infection (colony forming unit per milliliter), log10 of E. coli, Tumor necrosis factor alpha, Interleukin 6, VEGF, alanine aminotransferase, and aspartate aminotransferase levels and significant elevation in IL-10, IL-4, and HO-1. Immunohistochemical analysis of caspase-3 expression in lung tissue section showed low caspase-3 expression in cholecalciferol and low dose gamma radiation treated group. Histopathological examinations were performed in both lung and liver tissues which also emphasis the biochemical findings. Our results exhibit the importance of cholecalciferol and low dose gamma radiation in improving liver function and providing anti-inflammatory response in diseases causing cytokine storm.

LINC01002 functions as a ceRNA to regulate FRMD8 by sponging miR-4324 for the development of COVID-19

BACKGROUND

Syndrome coronavirus-2 (SARS-CoV-2) has developed various strategies to evade the antiviral impact of type I IFN. Non-structural proteins and auxiliary proteins have been extensively researched on their role in immune escape. Nevertheless, the detailed mechanisms of structural protein-induced immune evasion have not been well elucidated.

METHODS

Human alveolar basal epithelial carcinoma cell line (A549) was stimulated with polyinosinic-polycytidylic acid (PIC) and independently transfected with four structural proteins expression plasmids, including nucleocapsid (N), spike (S), membrane (M) and envelope (E) proteins. By RT-qPCR and ELISA, the structural protein with the most pronounced inhibitory effects on IFN-β induction was screened. RNA-sequencing (RNA-Seq) and two differential analysis strategies were used to obtain differentially expressed genes associated with N protein inhibition of IFN-β induction. Based on DIANA-LncBase and StarBase databases, the interactive competitive endogenous RNA (ceRNA) network for N protein-associated genes was constructed. By combining single-cell sequencing data (GSE158055), lncRNA-miRNA-mRNA axis was further determined. Finally, RT-qPCR was utilized to illustrate the regulatory functions among components of the ceRNA axis.

RESULTS

SARS-CoV-2 N protein inhibited IFN-β induction in human alveolar epithelial cells most significantly compared with other structural proteins. RNA-Seq data analysis revealed genes related to N protein inhibiting IFNs induction. The obtained 858 differentially expressed genes formed the reliable ceRNA network. The function of LINC01002-miR-4324-FRMD8 axis in the IFN-dominated immune evasion was further demonstrated through integrating single-cell sequencing data. Moreover, we validated that N protein could reverse the effect of PIC on LINC01002, FRMD8 and miR-4324 expression, and subsequently on IFN-β expression level. And LINC01002 could regulate the production of FRMD8 by inhibiting miR-4324.

CONCLUSION

SARS-CoV-2 N protein suppressed the induction of IFN-β by regulating LINC01002 which was as a ceRNA, sponging miR-4324 and participating in the regulation of FRMD8 mRNA. Our discovery provides new insights into early intervention therapy and drug development on SARS-CoV-2 infection.

Targeting chemokine-receptor mediated molecular signaling by ethnopharmacological approaches

ETHNOPHARMACOLOGICAL RELEVANCE

Infection and inflammation are critical to global human health status and the goal of current pharmacological interventions intends formulating medications/preventives as a measure to deal with this situation. Chemokines and their cognate receptors are major regulatory molecules in many of these ailments. Natural products have been a keen source to the drug development industry, every year contributing significantly to the growing list of FDA approved drugs. A multiverse of natural resource is employed as a part of curative regimen in folk/traditional/ethnomedicine which can be employed to discover, repurpose, and design potent medications for the diseases of clinical concern.

AIM OF THE STUDY

This review aims to systematically document the ethnopharmacologically active agents targeting the infectious-inflammatory diseases through the chemokine-receptor nexus.

MATERIALS AND METHODS

Articles related to chemokine/receptor modulating ethnopharmacological anti-inflammatory, anti-infectious natural sources, bioactive compounds, and formulations have been examined with special emphasis on women related diseases. The available literature has been thoroughly scrutinized for the application of traditional medicines in chemokine associated experimental methods, their regulatory outcomes, and pertinence to women's health wherever applicable. Moreover, the potential traditional regimens under clinical trials have been critically assessed.

RESULTS

A systematic and comprehensive review on the chemokine-receptor targeting ethnopharmaceutics from the available literature has been provided. The article discusses the implication of traditional medicine in the chemokine system dynamics in diverse infectious-inflammatory disorders such as cardiovascular diseases, allergic diseases, inflammatory diseases, neuroinflammation, and cancer. On this note, critical evaluation of the available data surfaced multiple diseases prevalent in women such as osteoporosis, rheumatoid arthritis, breast cancer, cervical cancer and urinary tract infection. Currently there is no available literature highlighting chemokine-receptor targeting using traditional medicinal approach from women's health perspective. Moreover, despite being potent in vitro and in vivo setups there remains a gap in clinical translation of these formulations, which needs to be strategically and scientifically addressed to pave the way for their successful industrial translation.

CONCLUSIONS

The review provides an optimistic global perspective towards the applicability of ethnopharmacology in chemokine-receptor regulated infectious and inflammatory diseases with special emphasis on ailments prevalent in women, consecutively addressing their current status of clinical translation and future directions.

Association of the C3953T (rs1143634) variant of the interleukin 1 beta gene with the features of a complicated course of COVID-19-associated pneumonia

BACKGROUND

The pro-inflammatory cytokine IL-1 plays an important role in severe COVID-19. A change in IL-1 production may be associated with a mutation in the IL1Β gene. Our study analyzed the impact of the IL1Β gene variants (rs1143634) on disease progression in patients with severe COVID-19 pneumonia, taking into account treatment strategies.

METHODS AND RESULTS

The study enrolled 117 patients with severe COVID-19 pneumonia. The IL1Β gene variants were identified using the polymerase chain reaction-restriction fragment length polymorphism method. In the group of patients, the following genotype frequencies were found based on the investigated rs1143634 variant of the IL1Β gene: CC-65.8%, CT-28.2%, and TT-6.0%. Our results showed that the group of patients with the T allele of the IL1Β gene had higher leukocyte counts (p = 0.040) and more pronounced lymphopenia (p = 0.007). It was determined that patients carrying the T allele stayed on ventilators significantly longer (p = 0.049) and required longer treatment with corticosteroids (p = 0.045).

CONCLUSION

Identifying variants of the IL1Β gene can be used as a predictive tool for assessing the severity of COVID-19 pneumonia and tailoring personalized treatment strategies. Further research with a larger patient cohort is required to validate these findings.

Decreased progenitor TCF1 + T-cells correlate with COVID-19 disease severity

COVID-19, caused by SARS-CoV-2, can lead to a severe inflammatory disease characterized by significant lymphopenia. However, the underlying cause for the depletion of T-cells in COVID-19 patients remains incompletely understood. In this study, we assessed the presence of different T-cell subsets in the progression of COVID-19 from mild to severe disease, with a focus on TCF1 expressing progenitor T-cells that are needed to replenish peripheral T-cells during infection. Our results showed a preferential decline in TCF1+ progenitor CD4 and CD8+ T-cells with disease severity. This decline was seen in various TCF1+ subsets including naive, memory and effector-memory cells, and surprisingly, was accompanied by a loss in cell division as seen by a marked decline in Ki67 expression. In addition, TCF1+ T-cells showed a reduction in pro-survival regulator, BcL2, and the appearance of a new population of TCF1 negative caspase-3 expressing cells in peripheral blood from patients with severe disease. The decline in TCF1+ T-cells was also seen in a subgroup of severe patients with vitamin D deficiency. Lastly, we found that sera from severe patients inhibited TCF1 transcription ex vivo which was attenuated by a blocking antibody against the cytokine, interleukin-12 (IL12). Collectively, our findings underscore the potential significance of TCF1+ progenitor T-cells in accounting for the loss of immunity in severe COVID-19 and outline an array of markers that could be used to identify disease progression.

The impact of SARS-CoV-2 mRNA vaccine on intracytoplasmic sperm injection outcomes at a fertility center in Iraq: A prospective cohort study

Background and Aims

Coronavirus disease 2019 (COVID-19) is a major public health problem that requires preventative vaccines. However, there is vaccine hesitancy among women of reproductive age in Iraq. This study aimed to investigate SARS-CoV-2 vaccination effects on intracytoplasmic sperm injection (ICSI) and related fertility parameters.

Methods

The study population comprised 54 infertile patients undergoing the ICSI procedure at a fertility clinic: vaccinated (n = 17) and non-vaccinated (n = 37). SARS-CoV-2-IgG/mL was assayed in follicular fluid from patients. Fertility parameters were assessed using oocyte and embryo quality and pregnancy outcomes between study groups, with respect to the time interval from vaccination to ova pick up.

Results

There were no significant differences between non-vaccinated and vaccinated groups in respect of oocytes quality with regard to the mean number of picked up oocytes (p = 0.564), abnormal oocyte (p = 0.827), oocytes metaphase I and II (p = 0.306; p = 0.165), germinal vesicles (p = 0.076), grade I, II, and III fertilized oocytes (p > 0.05), and for maturation rate (p = 0.13). There were also no significant differences (p > 0.05) in embryo quality parameters with the mean number of grade I, II, and III fertilized oocytes and the fertilization rate, the number of transferred embryo (0.086). There were no significant differences between vaccinated and unvaccinated groups with respect to follicular fluid SARS-CoV-2-IgG (p = 0.854), and pregnancy outcomes (p = 0.550).

Conclusions

The COVID-19 mRNA vaccine has no effect on ICSI, fertility parameters, and pregnancy outcome.

The unique ORF8 protein from SARS-CoV-2 binds to human dendritic cells and induces a hyper-inflammatory cytokine storm

The novel coronavirus pandemic, first reported in December 2019, was caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 infection leads to a strong immune response and activation of antigen-presenting cells, which can elicit acute respiratory distress syndrome (ARDS) characterized by the rapid onset of widespread inflammation, the so-called cytokine storm. In response to viral infections, monocytes are recruited into the lung and subsequently differentiate into dendritic cells (DCs). DCs are critical players in the development of acute lung inflammation that causes ARDS. Here, we focus on the interaction of a specific SARS-CoV-2 open reading frame protein, ORF8, with DCs. We show that ORF8 binds to DCs, causes pre-maturation of differentiating DCs, and induces the secretion of multiple proinflammatory cytokines by these cells. In addition, we identified DC-SIGN as a possible interaction partner of ORF8 on DCs. Blockade of ORF8 leads to reduced production of IL-1β, IL-6, IL-12p70, TNF-α, MCP-1 (also named CCL2), and IL-10 by DCs. Therefore, a neutralizing antibody blocking the ORF8-mediated cytokine and chemokine response could be an improved therapeutic strategy against SARS-CoV-2.

Implication of viruses in the etiology of preeclampsia

Preeclampsia is one of the most common disorders that poses threat to both mothers and neonates and a major contributor to perinatal morbidity and mortality worldwide. Viral infection during pregnancy is not typically considered to cause preeclampsia; however, syndromic nature of preeclampsia etiology and the immunomodulatory effects of viral infections suggest that microbes could trigger a subset of preeclampsia. Notably, SARS-CoV-2 infection is associated with an increased risk of preeclampsia. Herein, we review the potential role of viral infections in this great obstetrical syndrome. According to in vitro and in vivo experimental studies, viral infections can cause preeclampsia by introducing poor placentation, syncytiotrophoblast stress, and/or maternal systemic inflammation, which are all known to play a critical role in the development of preeclampsia. Moreover, clinical and experimental investigations have suggested a link between several viruses and the onset of preeclampsia via multiple pathways. However, the results of experimental and clinical research are not always consistent. Therefore, future studies should investigate the causal link between viral infections and preeclampsia to elucidate the mechanism behind this relationship and the etiology of preeclampsia itself.

Morphology and Function of Red Blood Cells in COVID-19 Patients: Current Overview 2023

In severe cases, SARS-CoV-2 infection leads to severe respiratory failure. Although angiotensin-converting enzyme 2 (ACE2) receptors are not expressed in red blood cells, SARS-CoV-2 can interact with red blood cells (RBCs) via several receptors or auxiliary membrane proteins. Recent data show that viral infection causes significant damage to the RBCs, altering their morphology, deformability, and aggregability. Loss of RBC deformability and/or increased aggregability favors the development of thrombotic processes in the microcirculation, as has been described to occur in COVID-19 patients. In addition, many patients also develop systemic endotheliitis associated with generalized coagulopathy. This manifests itself clinically as obstructive microthrombi in the area of the medium and smallest vessels, which can affect all internal organs. It is thought that such changes in the RBCs may contribute to the microangiopathy/microthrombosis associated with COVID-19 and may result in impaired capillary blood flow and tissue oxygenation.

Alveolar cytokines and interferon autoantibodies in COVID-19 ARDS

Background

Type I interferon (IFN-I) and IFN autoantibodies play a crucial role in controlling SARS-CoV-2 infection. The levels of these mediators have only rarely been studied in the alveolar compartment in patients with COVID-19 acute respiratory distress syndrome (CARDS) but have not been compared across different ARDS etiologies, and the potential effect of dexamethasone (DXM) on these mediators is not known.

Methods

We assessed the integrity of the alveolo-capillary membrane, interleukins, type I, II, and III IFNs, and IFN autoantibodies by studying the epithelial lining fluid (ELF) volumes, alveolar concentration of protein, and ELF-corrected concentrations of cytokines in two patient subgroups and controls.

Results

A total of 16 patients with CARDS (four without and 12 with DXM treatment), eight with non-CARDS, and 15 healthy controls were included. The highest ELF volumes and protein levels were observed in CARDS. Systemic and ELF-corrected alveolar concentrations of interleukin (IL)-6 appeared to be particularly low in patients with CARDS receiving DXM, whereas alveolar levels of IL-8 were high regardless of DXM treatment. Alveolar levels of IFNs were similar between CARDS and non-CARDS patients, and IFNα and IFNω autoantibody levels were higher in patients with CARDS and non-CARDS than in healthy controls.

Conclusions

Patients with CARDS exhibited greater alveolo-capillary barrier disruption with compartmentalization of IL-8, regardless of DXM treatment, whereas systemic and alveolar levels of IL-6 were lower in the DXM-treated subgroup. IFN-I autoantibodies were higher in the BALF of CARDS patients, independent of DXM, whereas IFN autoantibodies in plasma were similar to those in controls.

Immunomodulatory Effects of Vitamin D and Zinc on Viral Infection

Several nutrients are crucial in enhancing the immune system and preserving the structural integrity of bodily tissue barriers. Vitamin D (VD) and zinc (Zn) have received considerable interest due to their immunomodulatory properties and ability to enhance the body's immune defenses. Due to their antiviral, anti-inflammatory, antioxidative, and immunomodulatory properties, the two nutritional powerhouses VD and Zn are crucial for innate and adaptive immunity. As observed with COVID-19, deficiencies in these micronutrients impair immune responses, increasing susceptibility to viral infections and severe disease. Ensuring an adequate intake of VD and Zn emerges as a promising strategy for fortifying the immune system. Ongoing clinical trials are actively investigating their potential therapeutic advantages. Beyond the immediate context of the pandemic, these micronutrients offer valuable tools for enhancing immunity and overall well-being, especially in the face of future viral threats. This analysis emphasizes the enduring significance of VD and Zn as both treatment and preventive measures against potential viral challenges beyond the current health crisis. The overview delves into the immunomodulatory potential of VD and Zn in combating viral infections, with particular attention to their effects on animals. It provides a comprehensive summary of current research findings regarding their individual and synergistic impacts on immune function, underlining their potential in treating and preventing viral infections. Overall, this overview underscores the need for further research to understand how VD and Zn can modulate the immune response in combatting viral diseases in animals.

Do chemokine/chemokine receptor axes play paramount parts in trafficking and oriented locomotion of monocytes/macrophages toward the lungs of COVID-19 infected patients? A systematic review

The COVID-19 (coronavirus disease 2019) is a well-defined viral infection, resulting from SARS-CoV-2 (severe acute respiratory syndrome- coronavirus-2). The innate immune system serves as the first line of defense to limit viral spreading and subsequently stimulate adaptive immune responses by the prominent aids of its cellular and molecular arms. Monocytes are defined as the most prominent innate immune cells (IICs) that are reactive against invading pathogens. These cells support host protection against the virus that is mediated by several non-specific mechanisms such as phagocytosis, producing antiviral enzymes, and recruitment of immune cells toward and into the infected tissues. They have the ability to egress from blood and migrate to the SARS-CoV-2 infected regions by the aid of some defense-related functions like chemotaxis, which is mediated by chemical compounds, e.g., chemokines. Chemokines, in addition to their related ligands are categorized within the most important and deserved agents involved in oriented trafficking of monocytes/macrophages towards and within the lung parenchyma in both steady state and pathological circumstances, including COVID-19-raised infection. However, the overexpression of chemokines could have deleterious effects on various organs through the induction of cytokine storm and may be the most important leading mechanisms in the pathogenesis of COVID-19. Authors have aimed the current review article to describe present knowledge about the interplay between monocytes/macrophages and SARS-CoV-2 with a focus on the ability of IICs to migrate and home into the lung of COVID-19 patients through various chemokine-chemokine receptor axes to promote our understanding regarding this disease.

Intranasal Versus Intravenous Dexamethasone to Treat Hospitalized COVID-19 Patients: A Randomized Multicenter Clinical Trial

BACKGROUND

SARS-CoV2 induces flu-like symptoms that can rapidly progress to severe acute lung injury and even death. The virus also invades the central nervous system (CNS), causing neuroinflammation and death from central failure. Intravenous (IV) or oral dexamethasone (DXM) reduced 28 d mortality in patients who required supplemental oxygen compared to those who received conventional care alone. Through these routes, DMX fails to reach therapeutic levels in the CNS. In contrast, the intranasal (IN) route produces therapeutic levels of DXM in the CNS, even at low doses, with similar systemic bioavailability.

AIMS

To compare IN vs. IV DXM treatment in hospitalized patients with COVID-19.

METHODS

A controlled, multicenter, open-label trial. Patients with COVID-19 (69) were randomly assigned to receive IN-DXM (0.12 mg/kg for three days, followed by 0.6 mg/kg for up to seven days) or IV-DXM (6 mg/d for 10 d). The primary outcome was clinical improvement, as defined by the National Early Warning Score (NEWS) ordinal scale. The secondary outcome was death at 28 d between IV and IN patients. Effects of both treatments on biochemical and immunoinflammatory profiles were also recorded.

RESULTS

Initially, no significant differences in clinical severity, biometrics, and immunoinflammatory parameters were found between both groups. The NEWS-2 score was reduced, in 23 IN-DXM treated patients, with no significant variations in the 46 IV-DXM treated ones. Ten IV-DXM-treated patients and only one IN-DXM patient died.

CONCLUSIONS

IN-DMX reduced NEWS-2 and mortality more efficiently than IV-DXM, suggesting that IN is a more efficient route of DXM administration.

The impact of COVID-19 on cancer patients

The COVID-19 pandemic poses a significant challenge for individuals with compromised immune systems, such as patients with cancer, as they face a heightened susceptibility to severe infections compared to the general population. Such severe infections substantially increase the risk of morbidity and mortality among these patients. Notable risk factors for mortality include advanced age (> 70 years), current or past smoking history, advanced disease stage, the use of cytotoxic chemotherapy, and an Eastern Cooperative Oncology Group (ECOG) score of 2 or higher. Multiple types of vaccines have been developed and implemented, demonstrating remarkable efficacy in preventing infections. However, there have been observable reductions in their ability to elicit an immune response, particularly among individuals with hematological malignancies. The situation becomes more challenging due to the emergence of viral variants of concern (VOCs). Despite the increase in neutralizing antibody levels after vaccination, they remain lower in response to these evolving variants. The need for booster vaccinations has become apparent, particularly for this vulnerable population, due to the suboptimal immune response and waning of immunity post-vaccination. Examining and comprehending how the immune system reacts to various vaccination regimens for SARS-CoV-2 and its VOCs in cancer patients is crucial for designing clinical and public health strategies. This review aims to provide an updated overview of the effectiveness of COVID-19 vaccines in cancer patients, including those undergoing treatments such as hematopoietic stem cell transplantation (HCT) or chimeric antigen receptor (CAR) T cell therapy, by exploring the extent of both humoral and cellular immune responses to COVID-19 vaccination. Furthermore, it outlines risk factors and potential biomarkers that are associated with severe SARS-CoV-2 infection and vaccine responses, and offers suggestions for improving SARS-CoV-2 protection in cancer patients.

Changes in chemokine and growth factor levels may be useful biomarkers for monitoring disease severity in COVID-19 patients; a pilot study

Aim

The aim of the present study was to assess differences in the serum levels of chemokines and growth factors (GFs) between COVID-19 patients and healthy controls. The diagnostic utility of the analyzed proteins for monitoring the severity of the SARS-CoV- 2 infection based on the patients' MEWS scores was also assessed.

Materials and methods

The serum levels of chemokines and growth factors were analyzed in hospitalized COVID-19 patients (50 women, 50 men) with the use of the Bio-Plex Pro™ Human Cytokine Screening Panel (Biorad) and the Bio-Plex Multiplex system.

Results

The study demonstrated that serum levels of MIP-1α, RANTES, Eotaxin, CTACK, GRO-α, IP-10, MIG, basic-FGF, HGF, SCGF-β, G-CSF, M-CSF, SCF, MIF, LIF, and TRAIL were significant higher in COVID-19 patients than in the control group. The concentrations of CTACK, GRO-α, IP-10, MIG, basic-FGF, HGF, PDGF- BB, GM-CSF, SCF, LIF, and TRAIL were higher in asymptomatic/mildly symptomatic COVID-19 patients (stage 1) and COVID-19 patients with pneumonia without respiratory failure (stage 2). The receiver operating characteristic (ROC) analysis revealed that IP-10, MIF, MIG, and basic-FGF differentiated patients with COVID-19 from healthy controls with the highest sensitivity and specificity, whereas GM-CSF, basic-FGF, and MIG differentiated asymptomatic/mildly symptomatic COVID-19 patients (stage 1) from COVID-19 patients with pneumonia without respiratory failure (stage 2) with the highest sensitivity and specificity.

Conclusions

MIG, basic-FGF, and GM-CSF can be useful biomarkers for monitoring disease severity in patients with COVID-19.

Lipid Metabolism Modulation during SARS-CoV-2 Infection: A Spotlight on Extracellular Vesicles and Therapeutic Prospects

Extracellular vesicles (EVs) have a significant impact on the pathophysiological processes associated with various diseases such as tumors, inflammation, and infection. They exhibit molecular, biochemical, and entry control characteristics similar to viral infections. Viruses, on the other hand, depend on host metabolic machineries to fulfill their biosynthetic requirements. Due to potential advantages such as biocompatibility, biodegradation, and efficient immune activation, EVs have emerged as potential therapeutic targets against the SARS-CoV-2 infection. Studies on COVID-19 patients have shown that they frequently have dysregulated lipid profiles, which are associated with an increased risk of severe repercussions. Lipid droplets (LDs) serve as organelles with significant roles in lipid metabolism and energy homeostasis as well as having a wide range of functions in infections. The down-modulation of lipids, such as sphingolipid ceramide and eicosanoids, or of the transcriptional factors involved in lipogenesis seem to inhibit the viral multiplication, suggesting their involvement in the virus replication and pathogenesis as well as highlighting their potential as targets for drug development. Hence, this review focuses on the role of modulation of lipid metabolism and EVs in the mechanism of immune system evasion during SARS-CoV-2 infection and explores the therapeutic potential of EVs as well as application for delivering therapeutic substances to mitigate viral infections.

Vulture: cloud-enabled scalable mining of microbial reads in public scRNA-seq data

The rapidly growing collection of public single-cell sequencing data has become a valuable resource for molecular, cellular, and microbial discovery. Previous studies mostly overlooked detecting pathogens in human single-cell sequencing data. Moreover, existing bioinformatics tools lack the scalability to deal with big public data. We introduce Vulture, a scalable cloud-based pipeline that performs microbial calling for single-cell RNA sequencing (scRNA-seq) data, enabling meta-analysis of host-microbial studies from the public domain. In our benchmarking experiments, Vulture is 66% to 88% faster than local tools (PathogenTrack and Venus) and 41% faster than the state-of-the-art cloud-based tool Cumulus, while achieving comparable microbial read identification. In terms of the cost on cloud computing systems, Vulture also shows a cost reduction of 83% ($12 vs. ${\$}$70). We applied Vulture to 2 coronavirus disease 2019, 3 hepatocellular carcinoma (HCC), and 2 gastric cancer human patient cohorts with public sequencing reads data from scRNA-seq experiments and discovered cell type-specific enrichment of severe acute respiratory syndrome coronavirus 2, hepatitis B virus (HBV), and Helicobacter pylori-positive cells, respectively. In the HCC analysis, all cohorts showed hepatocyte-only enrichment of HBV, with cell subtype-associated HBV enrichment based on inferred copy number variations. In summary, Vulture presents a scalable and economical framework to mine unknown host-microbial interactions from large-scale public scRNA-seq data. Vulture is available via an open-source license at https://github.com/holab-hku/Vulture.

Levels of soluble TNF receptors (sTNFR1 and sTNFR2) increase with clinical worsening of patients and are related to COVID-19 mortality

The present study aimed to inspect the serum levels of the soluble receptors, sTNFR1 and sTNFR2, in patients with COVID-19. The large production of inflammatory cytokines is an essential process in the pathogenesis of COVID-19. TNF is a multifaceted proinflammatory cytokine which has soluble and membrane receptors. Thus, knowing the role of these receptors will help better understand this disease's immunopathogenesis. We included 131 patients confirmed for SARS-CoV-2, separated into three groups: ward patients without O2 support, group A (n = 14); ward patients with O2 support, group B (n = 85), and patients in an intensive care unit (ICU), group C (n = 32), making up the receptors dosed by flow cytometry. The results showed that sTNFR1 and sTNFR2 are associated with disease severity, being higher in group C when compared to group A. As for the levels of receptors and their relationship with the degree of lung involvement, we found higher values of sTNFR1 in patients in group 1 (pulmonary involvement < 25%), suggesting that inflammatory processes related to TNF are not necessarily associated with the primary site of infection. When we analysed the patients who passed away compared to those who recovered, both receptors significantly increased the mortality numbers. These findings suggest a relevant influence of soluble receptors in the inflammatory processes involved in the pathogenesis of COVID-19. Wherefore, we suggest using these receptors as biomarkers of severity and mortality of the disease.

Emerging Treatment Approaches for COVID-19 Infection: A Critical Review

In the present scenario, the SARS-CoV-2 virus has imposed enormous damage on human survival and the global financial system. It has been estimated that around 111 million people all around the world have been infected, and about 2.47 million people died due to this pandemic. The major symptoms were sneezing, coughing, cold, difficulty breathing, pneumonia, and multi-organ failure associated 1with SARS-CoV-2. Currently, two key problems, namely insufficient attempts to develop drugs against SARSCoV-2 and the lack of any biological regulating process, are mostly responsible for the havoc caused by this virus. Henceforth, developing a few novel drugs is urgently required to cure this pandemic. It has been noticed that the pathogenesis of COVID-19 is caused by two main events: infection and immune deficiency, that occur during the pathological process. Antiviral medication can treat both the virus and the host cells. Therefore, in the present review, the major approaches for the treatment have been divided into "target virus" and "target host" groups. These two mechanisms primarily rely on drug repositioning, novel approaches, and possible targets. Initially, we discussed the traditional drugs per the physicians' recommendations. Moreover, such therapeutics have no potential to fight against COVID-19. After that, detailed investigation and analysis were conducted to find some novel vaccines and monoclonal antibodies and conduct a few clinical trials to check their effectiveness against SARSCoV- 2 and mutant strains. Additionally, this study presents the most successful methods for its treatment, including combinatorial therapy. Nanotechnology was studied to build efficient nanocarriers to overcome the traditional constraints of antiviral and biological therapies.

Immune and metabolic perturbations in COVID-19-associated pulmonary mucormycosis: A transcriptome analysis of innate immune cells

BACKGROUND AND OBJECTIVES

The mechanisms underlying COVID-19-associated pulmonary mucormycosis (CAPM) remain unclear. We use a transcriptomic analysis of the innate immune cells to investigate the host immune and metabolic response pathways in patients with CAPM.

PATIENTS AND METHODS

We enrolled subjects with CAPM (n = 5), pulmonary mucormycosis (PM) without COVID-19 (n = 5), COVID-19 (without mucormycosis, n = 5), healthy controls (n = 5) without comorbid illness and negative for SARS-CoV-2. Peripheral blood samples from cases were collected before initiating antifungal therapy, and neutrophils and monocytes were isolated. RNA sequencing was performed using Illumina HiSeqX from monocytes and neutrophils. Raw reads were aligned with HISAT-2 pipeline and DESeq2 was used for differential gene expression. Gene ontology (GO) and metabolic pathway analysis were performed using Shiny GO application and R packages (ggplot2, Pathview).

RESULTS

The derangement of core immune and metabolic responses in CAPM patients was noted. Pattern recognition receptors, dectin-2, MCL, FcRγ receptors and CLEC-2, were upregulated, but signalling pathways such as JAK-STAT, IL-17 and CARD-9 were downregulated; mTOR and MAP-kinase signalling were elevated in monocytes from CAPM patients. The complement receptors, NETosis, and pro-inflammatory responses, such as S100A8/A9, lipocalin and MMP9, were elevated. The major metabolic pathways of glucose metabolism-glycolysis/gluconeogenesis, pentose phosphate pathway, HIF signalling and iron metabolism-ferroptosis were also upregulated in CAPM.

CONCLUSIONS

We identified significant alterations in the metabolic pathways possibly leading to cellular iron overload and a hyperglycaemic state. Immune responses revealed altered recognition, signalling, effector functions and a pro-inflammatory state in monocytes and neutrophils from CAPM patients.

Research Advances on the Role of Lipids in the Life Cycle of Human Coronaviruses

Coronaviruses (CoVs) are emerging pathogens with a significant potential to cause life-threatening harm to human health. Since the beginning of the 21st century, three highly pathogenic and transmissible human CoVs have emerged, triggering epidemics and posing major threats to global public health. CoVs are enveloped viruses encased in a lipid bilayer. As fundamental components of cells, lipids can play an integral role in many physiological processes, which have been reported to play important roles in the life cycle of CoVs, including viral entry, uncoating, replication, assembly, and release. Therefore, research on the role of lipids in the CoV life cycle can provide a basis for a better understanding of the infection mechanism of CoVs and provide lipid targets for the development of new antiviral strategies. In this review, research advances on the role of lipids in different stages of viral infection and the possible targets of lipids that interfere with the viral life cycle are discussed.

Exploring the Potential Association between COVID-19 and Thyroid Cancer: A Mendelian Randomization Study

In order to address the ongoing debate surrounding the potential link between COVID-19 and thyroid cancer, our study was specifically designed to investigate the association between these two factors. We acquired summary data from a genome-wide association study (GWAS) concerning COVID-19 susceptibility and severity of COVID-19 in the European population, with a focus on their relationship with thyroid cancer. We applied three distinct methodologies to evaluate the causality between COVID-19 and thyroid cancer, employing Mendelian randomization (MR)-Egger, weighted median (WM), and inverse variance-weighted (IVW) approaches. Furthermore, we utilized a variety of techniques to assess pleiotropy and heterogeneity, including the MR-Egger intercept, MR-pleiotropy residual sum and outlier method (PRESSO), and Cochran's Q test. The MR analysis revealed associations between the susceptibility of COVID-19 and thyroid cancer (IVW odds ratio [OR]: 2.826, 95% confidence interval [CI]: [0.842, 9.483], P = 0.093) as well as between the risk of COVID-19 hospitalization and thyroid cancer (IVW OR: 1.630, 95% CI: [1.050, 2.529], P = 0.029). However, the relationship between COVID-19 and the occurrence of severe thyroid cancer cases was less evident (IVW OR: 1.061, 95% CI: [0.575, 1.956], P = 0.850). Our sensitivity analyses did not reveal any signs of horizontal pleiotropy or heterogeneity. Our MR study provided compelling evidence supporting a causal connection between the risk of COVID-19 hospitalization and thyroid cancer. Nevertheless, the MR results derived from genetic data do not support a causal link between susceptibility to COVID-19 and the risk of thyroid cancer or between very severe cases of COVID-19 and the risk of thyroid cancer. These findings have significant implications for further investigations into the impact of COVID-19 on health and the etiology of thyroid cancer.

Spinal cord infarction attributed to SARS-CoV-2, with post-acute sequelae of COVID-19: A case report

BACKGROUND

While stroke and lower extremity venous thromboemboli have been commonly reported following acute infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spinal cord infarction or ischemia has been extremely rare. Findings of long coronavirus disease (COVID) in this select population have not been studied.

CASE SUMMARY

We present the case of a 70-year-old female with sudden onset of trunk and lower extremity sensorimotor loss due to spinal cord infarction, attributed to acute infection with SARS-CoV-2. Diagnostic work up confirmed a T3 complete (ASIA impairment Scale A) paraplegia resulting from a thrombotic infarct. Her reported myalgias, neuropathic pain, spasticity, bladder spasms, and urinary tract infections exceeded the frequency and severity of many spinal cord injury (SCI) individuals of similar age and degree of neurologic impairment. In her first year after contracting COVID-19, she underwent 2 separate inpatient rehabilitation courses, but also required acute hospitalization 6 additional times for subsequent infections or uncontrolled pain. Yet other complications of complete non-traumatic SCI (NTSCI), including neurogenic bowel and temperature hypersensitivity, were mild, and pressure injuries were absent. She has now transitioned from the acute to chronic phase of spinal cord injury care, with subsequent development of post-acute sequelae of SARS-CoV-2 infection (PASC).

CONCLUSION

This individual experienced significant challenges with the combined effects of acute T3 NTSCI and acute COVID-19, with subsequent progression to PASC.

A multi-epitope/CXCL11 prime/pull coronavirus mucosal vaccine boosts the frequency and the function of lung-resident memory CD4+ and CD8+ T cells and enhanced protection against COVID-19-like symptoms and death caused by SARS-CoV-2 infection

IMPORTANCE

Although the current rate of SARS-CoV-2 infections has decreased significantly, COVID-19 still ranks very high as a cause of death worldwide. As of October 2023, the weekly mortality rate is still at 600 deaths in the United States alone, which surpasses even the worst mortality rates recorded for influenza. Thus, the long-term outlook of COVID-19 is still a serious concern outlining the need for the next-generation vaccine. This study found that a prime/pull coronavirus vaccine strategy increased the frequency of functional SARS-CoV-2-specific CD4+ and CD8+ memory T cells in the lungs of SARS-CoV-2-infected triple transgenic HLA-DR*0101/HLA-A*0201/hACE2 mouse model, thereby resulting in low viral titer and reduced COVID-19-like symptoms.

Cytokine profile and antioxidants status in the moderate and severe COVID-19 patients: a trial of ozone therapy impact as a medicinal supplement

BACKGROUND

Complementary ozone therapy has been identified as a revolutionary medical technique for a number of goals and ailments. At the present, it has been shown that ozone has medicinal qualities, such as antibacterial, antifungal, and antiparasitic properties. Coronavirus (SARS-CoV-2) is quickly spread over the globe. Cytokine storms and oxidative stress seem to play a substantial role in the most of acute attacks of the disease. The aim of this research was to assess the therapeutic advantages of complementary ozone therapy on the cytokine profile and antioxidant status in COVID-19 patients.

METHODS

The statistical sample of this study included two hundred patients with COVID-19. One hundred COVID-19 patients (treatment group) received 240 ml of the patient's blood and an equal volume of O2/O3 gas at a concentration of 35-50 μg/ml daily, which gradually increased in concentration, and were kept for 5-10 days and one hundred patients (control group) received standard treatment. The secretion levels of IL-6, TNF-α, IL-1β, IL-10 cytokines, SOD, CAT and GPx were compared between control patients (standard treatment) and standard treatment plus intervention (ozone) before and after treatment.

RESULTS

The findings indicated a significant decrease in the level of IL-6, TNF-α, IL-1β in group receiving complementary ozone therapy in compared with control group. Furthermore, a significant increase was found in the level of IL-10 cytokine. Moreover, SOD, CAT and GPx levels revealed a significant increase in complementary ozone therapy group compared to control group.

CONCLUSIONS

Our results revealed that complementary ozone therapy can be used as a medicinal complementary therapy to reduce and control inflammatory cytokines and oxidative stress status in patients with COVID-19 as revealed its antioxidant and anti-inflammatory effects.

Homeostatic chemokines as putative therapeutic targets in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a fatal chronic interstitial lung disease (ILD) that affects lung mechanical functions and gas exchange. IPF is caused by increased fibroblast activity and collagen deposition that compromise the alveolar-capillary barrier. Identifying an effective therapy for IPF remains a clinical challenge. Chemokines are key proteins in cell communication that have functions in immunity as well as in tissue homeostasis, damage, and repair. Chemokine receptor signaling induces the activation and proliferation of lung-resident cells, including alveolar macrophages (AMs) and fibroblasts. AMs are an important source of chemokines and cytokines during IPF. We highlight the complexity of this system and, based on insights from genetic and transcriptomic studies, propose a new role for homeostatic chemokine imbalance in IPF, with implications for putative therapeutic targets.

hWJMSCs inhibit inflammation and apoptosis in an ARDS cell model

Acute respiratory distress syndrome (ARDS) is a type of lung failure caused by fluids and hypoxemia. Mesenchymal stem cells (MSCs) have been shown to decrease levels of pro-inflammatory mediators and inflammatory cells. These cells have anti-inflammatory, anti-apoptotic, and anti-microbial activity, and protect against lung injury.

Objective

This research evaluated the potential of human Wharton's jelly MSCs (hWJMSCs) to inhibit inflammation and apoptosis in lipopolysaccharide (LPS)-induced rat lung cells (L2).

Methods

hWJMSC treatment in LPS-induced rat lung cells was performed with 1:1, 1:5, 1:10, or 1:25 ratios of hWJMSCs to L2 cells. The gene expression of angiotensin-converting enzyme-2 (ACE-2), receptor for advanced glycation end products (RAGE), nuclear factor kappa B (NFκB), and C-X-C motif chemokine ligand-9 (CXCL-9) was quantified with RT-PCR, and the levels of C-reactive protein (CRP), interleukin-12 (IL-12), and tumor necrosis factor-alpha (TNF-α) were measured with ELISA.

Results

hWJMSCs increased ACE-2 gene expression, and decreased CXCL-9, NFκB, and RAGE gene expression. The treatment also suppressed CRP, TNF-α, and IL-12 levels, and increased the percentage of live cells, but decreased the percentages of necrotic cells and apoptotic cells in inflammatory rat lung cells, which served as an ARDS cell model.

Conclusion

Co-culture of hWJMSCs and L2 cells mitigated inflammation through increasing ACE-2 gene expression, and decreasing CXCL-9, NFκB, and RAGE gene expression; decreasing TNF-α and CRP protein levels; and decreasing necrosis, and early and late apoptosis. A co-culture ratio of 1:1 was most effective.

Does tocilizumab have an effect on the clinical outcomes in COVID-19 patients? A meta-analysis of randomized control trials

BACKGROUND

This meta-analysis was conducted to investigate the impact of tocilizumab on clinical outcomes associated with COVID-19.

METHODS

A comprehensive search was conducted across Scopus, PubMed (Medline), Cochrane Library, EMBASE (Elsevier), ClinicalTrials.gov, and Web of Sciences to identify pertinent studies published until May 2022. The primary search terms included "tocilizumab" and "COVID-19". Following the formulation of the search strategy, all identified studies were screened, and the data extraction process was initiated. Subsequently, the Cochrane risk of bias checklist was employed to evaluate the risk of bias. The effects of tocilizumab were assessed utilizing the pooled risk ratio (RR) and the fixed effect model in STATA (version 17).

RESULTS

In this meta-analysis, we analyzed 17 clinical trial studies to assess the impact of tocilizumab on mortality in patients with COVID-19. The pooled risk ratio (RR) for mortality was 0.93 (RR: 0.93; 95% CI: 0.86, 1.00; I2: 72.39%; P value: 0.001). The findings indicated that tocilizumab use was associated with a 4% increase in ICU hospitalization (RR: 1.04; 95% CI: 0.90, 1.20; I2: 0.00%; P value: 0.65). Additionally, tocilizumab administration was linked to a 2% reduction in the requirement for a ventilator (RR: 0.98; 95% CI: 0.90, 1.08; I2: 26.87%; P value: 0.16).

CONCLUSION

The administration of tocilizumab during the COVID-19 pandemic, prescribed to patients with the virus, exerted a noteworthy impact on reducing outcomes associated with COVID-19.

HDL-Related Parameters and COVID-19 Mortality: The Importance of HDL Function

COVID-19, caused by the SARS-CoV-2 coronavirus, emerged as a global pandemic in late 2019, resulting in significant global public health challenges. The emerging evidence suggests that diminished high-density lipoprotein (HDL) cholesterol levels are associated with the severity of COVID-19, beyond inflammation and oxidative stress. Here, we used nuclear magnetic resonance spectroscopy to compare the lipoprotein and metabolic profiles of COVID-19-infected patients with non-COVID-19 pneumonia. We compared the control group and the COVID-19 group using inflammatory markers to ensure that the differences in lipoprotein levels were due to COVID-19 infection. Our analyses revealed supramolecular phospholipid composite (SPC), phenylalanine, and HDL-related parameters as key discriminators between COVID-19-positive and non-COVID-19 pneumonia patients. More specifically, the levels of HDL parameters, including apolipoprotein A-I (ApoA-I), ApoA-II, HDL cholesterol, and HDL phospholipids, were significantly different. These findings underscore the potential impact of HDL-related factors in patients with COVID-19. Significantly, among the HDL-related metrics, the cholesterol efflux capacity (CEC) displayed the strongest negative association with COVID-19 mortality. CEC is a measure of how well HDL removes cholesterol from cells, which may affect the way SARS-CoV-2 enters cells. In summary, this study validates previously established markers of COVID-19 infection and further highlights the potential significance of HDL functionality in the context of COVID-19 mortality.

Mapping the Lipid Signatures in COVID-19 Infection: Diagnostic and Therapeutic Solutions

The COVID-19 pandemic ignited research centered around the identification of robust biomarkers and therapeutic targets. SARS-CoV-2, the virus responsible, hijacks the metabolic machinery of the host cells. It relies on lipids and lipoproteins of host cells for entry, trafficking, immune evasion, viral replication, and exocytosis. The infection causes host cell lipid metabolic remodelling. Targeting lipid-based processes is thus a promising strategy for countering COVID-19. Here, we review the role of lipids in the different steps of the SARS-CoV-2 pathogenesis and identify lipid-centric targetable avenues. We discuss lipidome changes in infected patients and their relevance as potential clinical diagnostic or prognostic biomarkers. We summarize the emerging direct and indirect therapeutic approaches for targeting COVID-19 using lipid-inspired approaches. Given that viral protein-targeted therapies may become less effective due to mutations in emerging SARS-CoV-2 variants, lipid-inspired interventions may provide additional and perhaps better means of combating this and future pandemics.

COVID myocarditis: a review of the literature

Myocarditis is a potentially fatal complication of coronavirus disease 2019 (COVID-19), which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. COVID-19 myocarditis appears to have distinct inflammatory characteristics that distinguish it from other viral etiologies. COVID-19 myocarditis can present with symptoms ranging from dyspnea and chest pain to acute heart failure and death. It is critical to detect any cases of myocarditis, especially fulminant myocarditis, which can be characterized by signs of heart failure and arrhythmias. Serial troponins, echocardiography, and electrocardiograms should be performed as part of the initial workup for suspected myocarditis. The second step in detecting myocarditis is cardiac magnetic resonance imaging and endomyocardial biopsy. Treatment for COVID-19 myocarditis is still debatable; however, combining intravenous immunoglobulins and corticosteroids may be effective, especially in cases of fulminant myocarditis. Overall, more research is needed to determine the incidence of COVID-19 myocarditis , and the use of intravenous immunoglobulins and corticosteroids in combination requires large randomized controlled trials to determine efficacy. The purpose of this review is to summarize current evidence on the subject. This review aims to summarise current evidence on this topic.

Immunosenescence and Inflammaging in COVID-19

Despite knowledge gaps in understanding the full spectrum of the hyperinflammatory phase caused by SARS-CoV-2, according to the World Health Organization (WHO), COVID-19 is still the leading cause of death worldwide. Susceptible people to severe COVID-19 are those with underlying medical conditions or those with dysregulated and senescence-associated immune responses. As the immune system undergoes aging in the elderly, such drastic changes predispose them to various diseases and affect their responsiveness to infections, as seen in COVID-19. At-risk groups experience poor prognosis in terms of disease recovery. Changes in the quantity and quality of immune cell function have been described in numerous literature sites. Impaired immune cell function along with age-related metabolic changes can lead to features such as hyperinflammatory response, immunosenescence, and inflammaging in COVID-19. Inflammaging is related to the increased activity of the most inflammatory factors and is the main cause of age-related diseases and tissue failure in the elderly. Since hyperinflammation is a common feature of most severe cases of COVID-19, this pathway, which is not fully understood, leads to immunosenescence and inflammaging in some individuals, especially in the elderly and those with comorbidities. In this review, we shed some light on the age-related abnormalities of innate and adaptive immune cells and how hyperinflammatory immune responses contribute to the inflammaging process, leading to clinical deterioration. Further, we provide insights into immunomodulation-based therapeutic approaches, which are potentially important considerations in vaccine design for elderly populations.

Comparing the recurrence of audio-vestibular disorders following breakthrough infection of COVID-19 vs. those following vaccine administration

PURPOSE

The term "breakthrough infection" of COVID-19 indicates that subjects who previously received COVID-19 vaccination became infected with COVID-19. This study compared the recurrence of audio-vestibular disorders following breakthrough infection of COVID-19 vs. those following vaccine administration.

PATIENTS AND METHODS

Fifty patients with previous known audio-vestibular disorders visited our clinic due to recurrence of inner ear symptoms following breakthrough infection of COVID-19 and were assigned to Group A. Another 50 patients who had recurrent inner ear symptoms following COVID-19 vaccination were assigned to Group B for comparison. The post-breakthrough infection interval is defined from date of breakthrough infection to the onset of inner ear symptoms, while the post-vaccination interval means the time from date of vaccination to the onset of inner ear symptoms. These two intervals were calculated and then compared.

RESULTS

The time from latest vaccination to the breakthrough infection of COVID-19 was 4 m (median), likely due to waning of IgG response. To the onset of inner ear symptoms, the post-breakthrough infection interval was 40d (median) for Group A, which was significantly longer than 10d (median) of the post-vaccination interval for Group B.

CONCLUSION

The post-breakthrough infection interval (median, 40d) is significantly longer than the post-vaccination interval (median, 10d) to exacerbate pre-existing audio-vestibular disorders. The reason is probably because an interval of 40d is related to IgG peak response following COVID-19 breakthrough infection, while that of 10d is responsible for IgG production after COVID-19 vaccination.

Is neuropilin-1 the neuroimmune initiator of multi-system hyperinflammation in COVID-19?

A major immunopathological feature of Coronavirus disease-2019 (COVID-19) is excessive inflammation in the form of "cytokine storm". The storm is characterized by injurious levels of cytokines which form a complicated network damaging different organs, including the lungs and the brain. The main starter of "cytokine network" hyperactivation in COVID-19 has not been discovered yet. Neuropilins (NRPs) are transmembrane proteins that act as neuronal guidance and angiogenesis modulators. The crucial function of NRPs in forming the nervous and vascular systems has been well-studied. NRP1 and NRP2 are the two identified homologs of NRP. NRP1 has been shown as a viral entry pathway for SARS-CoV2, which facilitates neuroinvasion by the virus within the central or peripheral nervous systems. These molecules directly interact with various COVID-19-related molecules, such as specific regions of the spike protein (major immune element of SARS-CoV2), vascular endothelial growth factor (VEGF) receptors, VEGFR1/2, and ANGPTL4 (regulator of vessel permeability and integrity). NRPs mainly play a role in hyperinflammatory injury of the CNS and lungs, and also the liver, kidney, pancreas, and heart in COVID-19 patients. New findings have suggested NRPs good candidates for pharmacotherapy of COVID-19. However, therapeutic targeting of NRP1 in COVID-19 is still in the preclinical phase. This review presents the implications of NRP1 in multi-organ inflammation-induced injury by SARS-CoV2 and provides insights for NRP1-targeting treatments for COVID-19 patients.

From 'mental fog' to post-acute COVID-19 syndrome's executive function alteration: Implications for clinical approach

A common symptom of the neuropsychiatric Post-Acute COVID-19 syndrome (neuro-PACS) is the so called 'brain fog'. Patients describe the brain fog as problems with attention, memory and mental fatigue. Brain fog is experienced by 9-55% of people for months after having contracted SARS-CoV-2 virus. Several theories have been proposed to explain PACS's brain fog, including a neuroinflammatory hypothesis, but the hypothesis remains to be proven. Here, we examined inflammatory and immunological blood profile in a cohort of patients with PACS to investigate the association between executive functions and blood inflammatory markers. Executive function was assessed by the Trail Making Test (TMT) Part A and Part B, as well as the Barkley Deficits in Executive Functioning Scale (BDEFS), in 71 patients (36 men), average age of 40 years (range: 15-82, SD: 15.7). Impairment in executive functioning (BDEFS scores and TMT B scores) correlated with increased levels of Interleukin-6 (IL-6), fibrinogen and ferritin. Moreover, elevated levels of Il-6, fibrinogen, ferritin, tumor necrosis factor-alpha and C-reactive protein have been observed in PACS. These findings demonstrate that PACS is characterized by the presence of an immuno-inflammatory process, which is associated with diminished executive functioning. Here, we argue in favour of a shift from the non-descriptive definition of 'mental fog' to a characterization of a subtype of PACS, associated with alteration in executive functioning. Implication for clinical settings and prevention are discussed.

Reduced SARS-CoV-2 mRNA vaccine immunogenicity and protection in mice with diet-induced obesity and insulin resistance

BACKGROUND

Obesity and type 2 diabetes mellitus (T2DM) are associated with an increased risk of severe outcomes from infectious diseases, including coronavirus disease 2019. These conditions are also associated with distinct responses to immunization, including an impaired response to widely used severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccines.

OBJECTIVE

We sought to establish a connection between reduced immunization efficacy via modeling the effects of metabolic diseases on vaccine immunogenicity that is essential for the development of more effective vaccines for this distinct vulnerable population.

METHODS

A murine model of diet-induced obesity and insulin resistance was used to model the effects of comorbid T2DM and obesity on vaccine immunogenicity and protection.

RESULTS

Mice fed a high-fat diet (HFD) developed obesity, hyperinsulinemia, and glucose intolerance. Relative to mice fed a normal diet, HFD mice vaccinated with a SARS-CoV-2 mRNA vaccine exhibited significantly lower anti-spike IgG titers, predominantly in the IgG2c subclass, associated with a lower type 1 response, along with a 3.83-fold decrease in neutralizing titers. Furthermore, enhanced vaccine-induced spike-specific CD8+ T-cell activation and protection from lung infection against SARS-CoV-2 challenge were seen only in mice fed a normal diet but not in HFD mice.

CONCLUSIONS

The study demonstrated impaired immunity following SARS-CoV-2 mRNA immunization in a murine model of comorbid T2DM and obesity, supporting the need for further research into the basis for impaired anti-SARS-CoV-2 immunity in T2DM and investigation of novel approaches to enhance vaccine immunogenicity among those with metabolic diseases.

Eicosanoids Signals in SARS-CoV-2 Infection: A Foe or Friend

SARS-CoV-2 mediated infection instigated a scary pandemic state since 2019. They created havoc comprising death, imbalanced social structures, and a wrecked global economy. During infection, the inflammation and associated cytokine storm generate a critical pathological situation in the human body, especially in the lungs. By the passage of time of infection, inflammatory disorders, and multiple organ damage happen which might lead to death, if not treated properly. Until now, many pathological parameters have been used to understand the progress of the severity of COVID-19 but with limited success. Bioactive lipid mediators have the potential of initiating and resolving inflammation in any disease. The connection between lipid storm and inflammatory states of SARS-CoV-2 infection has surfaced and got importance to understand and mitigate the pathological states of COVID-19. As the role of eicosanoids in COVID-19 infection is not well defined, available information regarding this issue has been accumulated to address the possible network of eicosanoids related to the initiation of inflammation, promotion of cytokine storm, and resolution of inflammation, and highlight possible strategies for treatment and drug discovery related to SARS-CoV-2 infection in this study. Understanding the involvement of eicosanoids in exploration of cellular events provoked by SARS-CoV-2 infection has been summarized as an important factor to deescalate any upcoming catastrophe imposed by the lethal variants of this micro-monster. Additionally, this study also recognized the eicosanoid based drug discovery, treatment, and strategies for managing the severity of SARS-COV-2 infection.

Single-cell transcriptomic analysis reveals a systemic immune dysregulation in COVID-19-associated pediatric encephalopathy

Unraveling the molecular mechanisms for COVID-19-associated encephalopathy and its immunopathology is crucial for developing effective treatments. Here, we utilized single-cell transcriptomic analysis and integrated clinical observations and laboratory examination to dissect the host immune responses and reveal pathological mechanisms in COVID-19-associated pediatric encephalopathy. We found that lymphopenia was a prominent characteristic of immune perturbation in COVID-19 patients with encephalopathy, especially those with acute necrotizing encephalopathy (AE). This was characterized a marked reduction of various lymphocytes (e.g., CD8+ T and CD4+ T cells) and significant increases in other inflammatory cells (e.g., monocytes). Further analysis revealed activation of multiple cell apoptosis pathways (e.g., granzyme/perforin-, FAS- and TNF-induced apoptosis) may be responsible for lymphopenia. A systemic S100A12 upregulation, primarily from classical monocytes, may have contributed to cytokine storms in patients with AE. A dysregulated type I interferon (IFN) response was observed which may have further exacerbated the S100A12-driven inflammation in patients with AE. In COVID-19 patients with AE, myeloid cells (e.g., monocytic myeloid-derived suppressor cells) were the likely contributors to immune paralysis. Finally, the immune landscape in COVID-19 patients with encephalopathy, especially for AE, were also characterized by NK and T cells with widespread exhaustion, higher cytotoxic scores and inflammatory response as well as a dysregulated B cell-mediated humoral immune response. Taken together, this comprehensive data provides a detailed resource for elucidating immunopathogenesis and will aid development of effective COVID-19-associated pediatric encephalopathy treatments, especially for those with AE.

SARS-CoV-2 and Brain Health: New Challenges in the Era of the Pandemic

Respiratory viral infections have been found to have a negative impact on neurological functions, potentially leading to significant neurological impairment. The SARS-CoV-2 virus has precipitated a worldwide pandemic, posing a substantial threat to human lives. Growing evidence suggests that SARS-CoV-2 may severely affect the CNS and respiratory system. The current prevalence of clinical neurological issues associated with SARS-CoV-2 has raised significant concerns. However, there needs to be a more comprehensive understanding of the specific pathways by which SARS-CoV-2 enters the nervous system. Based on the available evidence, this review focuses on the clinical neurological manifestations of SARS-CoV-2 and the possible mechanisms by which SARS-CoV-2 invades the brain.

Type 2 diabetes and Covid-19: Lessons learnt, unanswered questions and hints for the future

Type 2 diabetes (T2DM) and COVID-19 represent a considerable burden of disease for patients and healthcare systems. New evidence is transpiring detailing the existence of a bidirectional relationship between T2DM and COVID-19. Alongside the acute influence of pre-existing T2DM on the course of COVID-19 and the exacerbation of dysglycemia following acute infection, long-term sequalae resulting from the synergistic interplay between the two is emerging, namely the development of COVID-induced diabetes and long-COVID in patients with pre-existing diabetes. This review presents our current understanding of the bidirectionality between these two conditions with a view to highlighting questions which remain unanswered and suggesting avenues for future research. In doing so, it emphasises critical gaps where concentrated research efforts are likely to yield the most beneficial improvements in understanding of the relationship between the two conditions, translating to tangible optimisations in care for the affected population.

Recurrent COVID-19 Infection in a Refractory/Classical Hodgkin's Lymphoma Patient Undergoing Autologous Stem Cell Transplantation: A Case Report

Patients with challenging hematological malignancies like classic Hodgkin lymphoma (cHL) can be further complicated when affected by a concurrent coronavirus disease-2019 (COVID-19) infection and often face unique and complex management and outcomes. In this case report, we describe a refractory or relapsed classic Hodgkin lymphoma patient with a recurrent infection of COVID-19 three times preceding chemotherapy. A 52-year-old female presented to our hospital with a second incidence of COVID-19 and a complaint of fever, anorexia, night sweats, and abdominal lymphadenopathy, for which she was diagnosed with mixed cellularity classic Hodgkin lymphoma. Three weeks later, in consideration of her manifestation of lung disease, which was due to her past medical history of airway hypersensitivity and abnormal pulmonary function test along with testing positive for COVID-19, she was started with the first-line chemotherapy of the brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine chemotherapy regimen, commonly referred to as Bv-AVD, without bleomycin. After six cycles of chemotherapy, at the end of treatment, positron emission tomography/computed tomography (PET/CT) revealed the progression of nodes in the abdomen and the development of new lymphadenopathy in the chest and right supraclavicular region. Hence, it was considered refractory Hodgkin's lymphoma, and the patient was referred for salvage therapy. She was started on salvage chemotherapy with brentuximab/bendamustine (BvB). Follow-up evaluations after two cycles of BvB continued to show newer lesions in the right sub-diaphragmatic area, internal mammary, and supraclavicular lymph nodes. Therefore, the patient was switched to pembrolizumab immunotherapy, a PD-1 inhibitor. After four cycles of pembrolizumab monotherapy, PET/CT showed significant improvement with a complete molecular response (CMR). Then, she was admitted for high-dose therapy/autologous stem cell transplantation (HDT/ASCT) after collecting stem cells. PET/CT: three months post-ASCT, she continued to be in a CMR with a Deauville score of 1. The patient was continued on pembrolizumab maintenance for six months afterward. Currently, the patient is healthy and doing well. COVID-19 patients with hematological malignancies may experience compromised viral elimination and a prolonged period of viral infection, which may also worsen the symptoms and outcomes and entitle them to comprehensive and extended care.

Correlation of serum interleukin-6 levels and neutrophil-lymphocyte ratio in the severity of COVID-19

Background: Interleukin-6 (IL-6) is a pro-inflammatory cytokine that is produced at varying levels in patients with coronavirus disease 2019 (COVID-19). The neutrophil-lymphocyte ratio (NLR) is one of the new inflammatory markers of COVID-19. This study aimed to evaluate the differences in IL-6 level and the NLR in mild and severe COVID-19 and assess their correlation with COVID-19 severity and the correlation of IL-6 and NLR in COVID-19. Methods: A total of 91 patients with COVID-19 were divided into mild (n = 57) and severe (n = 34) COVID-19 groups. IL-6 levels were measured using the electrochemiluminescence immunoassay method on Roche Cobas e411. The NLR was the ratio of the total neutrophil and lymphocyte counts from complete haematology on the Sysmex XS-800i. Data were analysed using the Kolmogorov-Smirnov, Mann-Whitney, receiver operating characteristic curve, chi-square and Spearman correlation tests. The statistical test was significant at p <0.05. Results: Serum IL-6 levels and NLR significantly differed in mild and severe COVID-19. The median (min-max) IL-6 levels for mild and severe COVID-19 were 3.59 (1.50-638.30) pg/mL and 28.82 (5.52-926.30) pg/mL, respectively (p <0.001). The median (min-max) NLR in mild and moderate COVID-19 was 2.18 (0.69-15.58) and 8.13 (2.24-30.90), respectively (p <0.001). The obtained cut-off values for IL-6 and NLR were >6.99 pg/mL and >4.18, with odds ratios of 29.29 and 26.19, respectively. A positive correlation was found between IL-6 and NLR and COVID-19 severity (r = 0.612; p <0.001). Conclusions: The results indicated that serum IL-6 levels and NLR are higher in severe COVID-19 than in mild COVID-19. Patients with IL-6 levels >6.99 pg/mL and NLR >4.18 are 29 and 26 times more likely to suffer from severe COVID-19, respectively. Serum IL-6 levels and NLR are strongly correlated with COVID-19 severity. Serum IL-6 levels correlate with NLR in COVID-19.

Heparanase inhibition leads to improvement in patients with acute gastrointestinal injuries induced by sepsis

BACKGROUND

Patients with sepsis are at high risk for acute gastrointestinal injury (AGI), but the diagnosis and treatment of AGI due to sepsis are unsatisfactory. Heparanase (HPA) plays an important role in septic AGI (S-AGI), but its specific mechanism is not completely understood, and few clinical reports are available.

AIM

To explore the effect and mechanism of HPA inhibition in S-AGI patients.

METHODS

In our prospective clinical trial, 48 patients with S-AGI were randomly assigned to a control group to receive conventional treatment, whereas 47 patients were randomly assigned to an intervention group to receive conventional treatment combined with low molecular weight heparin. AGI grade, sequential organ failure assessment score, acute physiology and chronic health evaluation II score, D-dimer, activated partial thromboplastin time (APTT), anti-Xa factor, interleukin-6, tumour necrosis factor-α, HPA, syndecan-1 (SDC-1), LC3B (autophagy marker), intestinal fatty acid binding protein, D-lactate, motilin, gastrin, CD4/CD8, length of intensive care unit (ICU) stay, length of hospital stay and 28-d survival on the 1st, 3rd and 7th d after treatment were compared. Correlations between HPA and AGI grading as well as LC3B were compared. Receiver operator characteristic (ROC) curves were generated to evaluate the diagnostic value of HPA, intestinal fatty acid binding protein and D-lactate in S-AGI.

RESULTS

Serum HPA and SCD-1 levels were significantly reduced in the intervention group compared with the control group (P < 0.05). In addition, intestinal fatty acid-binding protein, D-lactate, AGI grade, motilin, and gastrin levels and sequential organ failure assessment score were significantly decreased (P < 0.05) in the intervention group. However, LC3B, APTT, anti-Xa factor, and CD4/CD8 were significantly increased (P < 0.05) in the intervention group. No significant differences in interleukin-6, tumour necrosis factor-α, d-dimer, acute physiology and chronic health evaluation II score, length of ICU stay, length of hospital stay, or 28-d survival were noted between the two groups (P > 0.05). Correlation analysis revealed a significant negative correlation between HPA and LC3B and a significant positive correlation between HPA and AGI grade. ROC curve analysis showed that HPA had higher specificity and sensitivity in diagnosis of S-AGI.

CONCLUSION

HPA has great potential as a diagnostic marker for S-AGI. Inhibition of HPA activity reduces SDC-1 shedding and alleviates S-AGI symptoms. The inhibitory effect of HPA in gastrointestinal protection may be achieved by enhanced autophagy.

Discovery and pharmacophoric characterization of chemokine network inhibitors using phage-display, saturation mutagenesis and computational modelling

CC and CXC-chemokines are the primary drivers of chemotaxis in inflammation, but chemokine network redundancy thwarts pharmacological intervention. Tick evasins promiscuously bind CC and CXC-chemokines, overcoming redundancy. Here we show that short peptides that promiscuously bind both chemokine classes can be identified from evasins by phage-display screening performed with multiple chemokines in parallel. We identify two conserved motifs within these peptides and show using saturation-mutagenesis phage-display and chemotaxis studies of an exemplar peptide that an anionic patch in the first motif and hydrophobic, aromatic and cysteine residues in the second are functionally necessary. AlphaFold2-Multimer modelling suggests that the peptide occludes distinct receptor-binding regions in CC and in CXC-chemokines, with the first and second motifs contributing ionic and hydrophobic interactions respectively. Our results indicate that peptides with broad-spectrum anti-chemokine activity and therapeutic potential may be identified from evasins, and the pharmacophore characterised by phage display, saturation mutagenesis and computational modelling.

Blood ACE2 Protein Level Correlates with COVID-19 Severity

ACE2's impact on the severity of COVID-19 is widely discussed but still controversial. To estimate its role in aspects of the main risk factors and comorbidities, we involved post-COVID-19 patients in Ternopil region (Ukraine). The recruitment period was from July 2020 to December 2021. Medical records, treatment modalities, and outcomes were recorded and analyzed. The serum human ACE2 protein was measured with Cusabio ELISA kits (Houston, TX, USA). Statistical analysis was performed with SPSS21.0 software (SPSS Inc., Chicago, IL, USA). The level of the ACE2 serum protein was significantly higher (p < 0.001) in patients with mild symptoms compared to a more severe course of the disease, and inversely had changed from 1 to 90 days after recovery. In patients with mild COVID-19, ACE2 levels significantly decreased over time, while among critical patients, it increased by 34.1 percent. Such results could be explained by ACE2 shedding from tissues into circulation. Loss of the membrane-bound form of the enzyme decreases the virus' entry into cells. Our studies did not identify a sex-related ACE2 serum level correlation. The most common comorbidities were hypertension, cardiovascular diseases, respiratory diseases, and diabetes mellitus. All abovementioned comorbidities except respiratory diseases contribute to the severity of the disease and correlate with ACE2 blood serum levels.