IL-15 immunotherapy is a viable strategy for COVID-19

COVID-19 and Long COVID: Disruption of the Neurovascular Unit, Blood-Brain Barrier, and Tight Junctions

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), could affect brain structure and function. SARS-CoV-2 can enter the brain through different routes, including the olfactory, trigeminal, and vagus nerves, and through blood and immunocytes. SARS-CoV-2 may also enter the brain from the peripheral blood through a disrupted blood-brain barrier (BBB). The neurovascular unit in the brain, composed of neurons, astrocytes, endothelial cells, and pericytes, protects brain parenchyma by regulating the entry of substances from the blood. The endothelial cells, pericytes, and astrocytes highly express angiotensin converting enzyme 2 (ACE2), indicating that the BBB can be disturbed by SARS-CoV-2 and lead to derangements of tight junction and adherens junction proteins. This leads to increased BBB permeability, leakage of blood components, and movement of immune cells into the brain parenchyma. SARS-CoV-2 may also cross microvascular endothelial cells through an ACE2 receptor-associated pathway. The exact mechanism of BBB dysregulation in COVID-19/neuro-COVID is not clearly known, nor is the development of long COVID. Various blood biomarkers could indicate disease severity and neurologic complications in COVID-19 and help objectively diagnose those developing long COVID. This review highlights the importance of neurovascular and BBB disruption, as well as some potentially useful biomarkers in COVID-19, and long COVID/neuro-COVID.

Natural Killer Cell‐Derived Extracellular Vesicles as Potential Anti‐Viral Nanomaterials

In viral infections, natural killer (NK) cells exhibit anti-viral activity by inducing apoptosis in infected host cells and impeding viral replication through heightened cytokine release. Extracellular vesicles derived from NK cells (NK-EVs) also contain the membrane composition, homing capabilities, and cargo that enable anti-viral activity. These characteristics, and their biocompatibility and low immunogenicity, give NK-EVs the potential to be a viable therapeutic platform. This study characterizes the size, EV-specific protein expression, cell internalization, biocompatibility, and anti-viral miRNA cargo to evaluate the anti-viral properties of NK-EVs. After 48 h of NK-EV incubation in inflamed A549 lung epithelial cells, or conditions that mimic lung viral infections such as during COVID-19, cells treated with NK-EVs exhibit upregulated anti-viral miRNA cargo (miR-27a, miR-27b, miR-369-3p, miR-491-5p) compared to the non-treated controls and cells treated with control EVs derived from lung epithelial cells. Additionally, NK-EVs effectively reduce expression of viral RNA and pro-inflammatory cytokine (TNF-α, IL-8) levels in SARS-CoV-2 infected Vero E6 kidney epithelial cells and in infected mice without causing tissue damage while significantly decreasing pro-inflammatory cytokine compared to non-treated controls. Herein, this work elucidates the potential of NK-EVs as safe, anti-viral nanomaterials, offering a promising alternative to conventional NK cell and anti-viral therapies.

IL-15 as a key regulator in NK cell-mediated immunotherapy for cancer: From bench to bedside

Interleukin 15 (IL-15) has emerged as a crucial factor in the relationship between natural killer (NK) cells and immunotherapy for cancer. This review article aims to provide a comprehensive understanding of the role of IL-15 in NK cell-mediated immunotherapy. First, the key role of IL-15 signaling in NK cell immunity is discussed, highlighting its regulation of NK cell functions and antitumor properties. Furthermore, the use of IL-15 or its analogs in clinical trials as a therapeutic strategy for various cancers, including the genetic modification of NK cells to produce IL-15, has been explored. The potential of IL-15-based therapies, such as chimeric antigen receptor (CAR) T and NK cell infusion along with IL-15 in combination with checkpoint inhibitors and other treatments, has been examined. This review also addresses the challenges and advantages of incorporating IL-15 in cell-based immunotherapy. Additionally, unresolved questions regarding the detection and biological significance of the soluble IL-15/IL-15Rα complex, as well as the potential role of IL-15/IL-15Rα in human cancer and the immunological consequences of prolonged exposure to soluble IL-15 for NK cells, are discussed.

Sarcopenia augments the risk of excess weight on COVID-19 hospitalization: A prospective study using the Lifelines COVID-19 cohort

OBJECTIVE

We investigated the associations of sarcopenia alone, overweight or obesity, and sarcopenic overweight or obesity with COVID-19 hospitalization.

METHODS

Participants from the Lifelines COVID-19 cohort who were infected with COVID-19 were included in this study. Sarcopenia was defined as a relative deviation of muscle mass of ≤ -1.0 SD from the sex-specific mean 24-h urinary creatinine excretion. Overweight or obesity was defined as a body mass index ≥ 25 kg/m2. Sarcopenic overweight or obesity was defined as the presence of overweight or obesity and low muscle mass. COVID-19 hospitalization was self-reported. Logistic regression models were used to analyze the associations of sarcopenia alone, overweight or obesity, and sarcopenic overweight or obesity with COVID-19 hospitalization.

RESULTS

Of the 3594 participants infected with COVID-19 and recruited in this study, 173 had been admitted to the hospital. Compared with the reference group, individuals with overweight or obesity and sarcopenic overweight or obesity were 1.78-times and 2.09-times more likely to have been hospitalized for COVID-19, respectively, whereas sarcopenia alone did not increase the risk of COVID-19 hospitalization.

CONCLUSIONS

In this middle-aged population, sarcopenic overweight or obesity elevated the risk of hospitalization for COVID-19 in those infected with COVID-19 more than overweight or obesity alone. These data support the relevance of sarcopenic overweight or obesity as a risk factor beyond the geriatric setting and should be considered in risk stratification in future public health and vaccination campaigns.

M-CSF directs myeloid and NK cell differentiation to protect from CMV after hematopoietic cell transplantation

Therapies reconstituting autologous antiviral immunocompetence may represent an important prophylaxis and treatment for immunosuppressed individuals. Following hematopoietic cell transplantation (HCT), patients are susceptible to Herpesviridae including cytomegalovirus (CMV). We show in a murine model of HCT that macrophage colony-stimulating factor (M-CSF) promoted rapid antiviral activity and protection from viremia caused by murine CMV. M-CSF given at transplantation stimulated sequential myeloid and natural killer (NK) cell differentiation culminating in increased NK cell numbers, production of granzyme B and interferon-γ. This depended upon M-CSF-induced myelopoiesis leading to IL15Rα-mediated presentation of IL-15 on monocytes, augmented by type I interferons from plasmacytoid dendritic cells. Demonstrating relevance to human HCT, M-CSF induced myelomonocytic IL15Rα expression and numbers of functional NK cells in G-CSF-mobilized hematopoietic stem and progenitor cells. Together, M-CSF-induced myelopoiesis triggered an integrated differentiation of myeloid and NK cells to protect HCT recipients from CMV. Thus, our results identify a rationale for the therapeutic use of M-CSF to rapidly reconstitute antiviral activity in immunocompromised individuals, which may provide a general paradigm to boost innate antiviral immunocompetence using host-directed therapies.

De Novo Human Angiotensin-Converting Enzyme 2 Decoy NL-CVX1 Protects Mice From Severe Disease After Severe Acute Respiratory Syndrome Coronavirus 2 Infection

The emergence of novel variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) underscores the need to investigate alternative approaches to prevent infection and treat patients with coronavirus disease 2019. Here, we report the preclinical efficacy of NL-CVX1, a de novo decoy that blocks virus entry into cells by binding with nanomolar affinity and high specificity to the receptor-binding domain of the SARS-CoV-2 spike protein. Using a transgenic mouse model of SARS-CoV-2 infection, we showed that a single prophylactic intranasal dose of NL-CVX1 conferred complete protection from severe disease following SARS-CoV-2 infection. Multiple therapeutic administrations of NL-CVX1 also protected mice from succumbing to infection. Finally, we showed that infected mice treated with NL-CVX1 developed both anti-SARS-CoV-2 antibodies and memory T cells and were protected against reinfection a month after treatment. Overall, these observations suggest NL-CVX1 is a promising therapeutic candidate for preventing and treating severe SARS-CoV-2 infections.

Role of SARS-CoV-2 Spike-Protein-Induced Activation of Microglia and Mast Cells in the Pathogenesis of Neuro-COVID

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). About 45% of COVID-19 patients experience several symptoms a few months after the initial infection and develop post-acute sequelae of SARS-CoV-2 (PASC), referred to as "Long-COVID," characterized by persistent physical and mental fatigue. However, the exact pathogenetic mechanisms affecting the brain are still not well-understood. There is increasing evidence of neurovascular inflammation in the brain. However, the precise role of the neuroinflammatory response that contributes to the disease severity of COVID-19 and long COVID pathogenesis is not clearly understood. Here, we review the reports that the SARS-CoV-2 spike protein can cause blood-brain barrier (BBB) dysfunction and damage neurons either directly, or via activation of brain mast cells and microglia and the release of various neuroinflammatory molecules. Moreover, we provide recent evidence that the novel flavanol eriodictyol is particularly suited for development as an effective treatment alone or together with oleuropein and sulforaphane (ViralProtek®), all of which have potent anti-viral and anti-inflammatory actions.

Evolution of developmental and comparative immunology in poultry: The regulators and the regulated

Avian has a unique immune system that evolved in response to environmental pressures in all aspects of innate and adaptive immune responses, including localized and circulating lymphocytes, diversity of immunoglobulin repertoire, and various cytokines and chemokines. All of these attributes make birds an indispensable vertebrate model for studying the fundamental immunological concepts and comparative immunology. However, research on the immune system in birds lags far behind that of humans, mice, and other agricultural animal species, and limited immune tools have hindered the adequate application of birds as disease models for mammalian systems. An in-depth understanding of the avian immune system relies on the detailed studies of various regulated and regulatory mediators, such as cell surface antigens, cytokines, and chemokines. Here, we review current knowledge centered on the roles of avian cell surface antigens, cytokines, chemokines, and beyond. Moreover, we provide an update on recent progress in this rapidly developing field of study with respect to the availability of immune reagents that will facilitate the study of regulatory and regulated components of poultry immunity. The new information on avian immunity and available immune tools will benefit avian researchers and evolutionary biologists in conducting fundamental and applied research.

Alterations in the Kynurenine-Tryptophan Pathway and Lipid Dysregulation Are Preserved Features of COVID-19 in Hemodialysis

Coronavirus disease 2019 (COVID-19)-induced metabolic alterations have been proposed as a source for prognostic biomarkers and may harbor potential for therapeutic exploitation. However, the metabolic impact of COVID-19 in hemodialysis (HD), a setting of profound a priori alterations, remains unstudied. To evaluate potential COVID-19 biomarkers in end-stage kidney disease (CKD G5), we analyzed the plasma metabolites in different COVID-19 stages in patients with or without HD. We recruited 18 and 9 asymptomatic and mild, 11 and 11 moderate, 2 and 13 severely affected, and 10 and 6 uninfected HD and non-HD patients, respectively. Plasma samples were taken at the time of diagnosis and/or upon admission to the hospital and analyzed by targeted metabolomics and cytokine/chemokine profiling. Targeted metabolomics confirmed stage-dependent alterations of the metabolome in non-HD patients with COVID-19, which were less pronounced in HD patients. Elevated kynurenine levels and lipid dysregulation, shown by an increase in circulating free fatty acids and a decrease in lysophospholipids, could distinguish patients with moderate COVID-19 from non-infected individuals in both groups. Kynurenine and lipid alterations were also associated with ICAM-1 and IL-15 levels in HD and non-HD patients. Our findings support the kynurenine pathway and plasma lipids as universal biomarkers of moderate and severe COVID-19 independent of kidney function.

H7N9 avian influenza virus infection in men is associated with testosterone depletion

Human infections with H7N9 avian influenza A virus that emerged in East China in 2013 and caused high morbidity rates were more frequently detected in men than in women over the last five epidemic waves. However, molecular markers associated with poor disease outcomes in men are still unknown. In this study, we systematically analysed sex hormone and cytokine levels in males and females with laboratory-confirmed H7N9 influenza in comparison to H7N9-negative control groups as well as laboratory-confirmed seasonal H1N1/H3N2 influenza cases (n = 369). Multivariable analyses reveal that H7N9-infected men present with considerably reduced testosterone levels associated with a poor outcome compared to non-infected controls. Regression analyses reveal that testosterone levels in H7N9-infected men are negatively associated with the levels of several pro-inflammatory cytokines, such as IL-6 and IL-15. To assess whether there is a causal relationship between low testosterone levels and avian H7N9 influenza infection, we used a mouse model. In male mice, we show that respiratory H7N9 infection leads to a high viral load and inflammatory cytokine response in the testes as well as a reduction in pre-infection plasma testosterone levels. Collectively, these findings suggest that monitoring sex hormone levels may support individualized management for patients with avian influenza infections.

Adaptive immunity to SARS-CoV-2 infection: A systematic review

Background

There is evidence that the adaptive or acquired immune system is one of the crucial variables in differentiating the course of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This work aimed to analyze the immunopathological aspects of adaptive immunity that are involved in the progression of this disease.

Methods

This is a systematic review based on articles that included experimental evidence from in vitro assays, cohort studies, reviews, cross-sectional and case-control studies from PubMed, SciELO, MEDLINE, and Lilacs databases in English, Portuguese, or Spanish between January 2020 and July 2022.

Results

Fifty-six articles were finalized for this review. CD4+ T cells were the most resolutive in the health-disease process compared with B cells and CD8+ T lymphocytes. The predominant subpopulations of T helper lymphocytes (Th) in critically ill patients are Th1, Th2, Th17 (without their main characteristics) and regulatory T cells (Treg), while in mild cases there is an influx of Th1, Th2, Th17 and follicular T helper cells (Tfh). These cells are responsible for the secretion of cytokines, including interleukin (IL) - 6, IL-4, IL-10, IL-7, IL-22, IL-21, IL-15, IL-1α, IL-23, IL-5, IL-13, IL-2, IL-17, tumor necrosis factor alpha (TNF-α), CXC motivating ligand (CXCL) 8, CXCL9 and tumor growth factor beta (TGF-β), with the abovementioned first 8 inflammatory mediators related to clinical benefits, while the others to a poor prognosis. Some CD8+ T lymphocyte markers are associated with the severity of the disease, such as human leukocyte antigen (HLA-DR) and programmed cell death protein 1 (PD-1). Among the antibodies produced by SARS-CoV-2, Immunoglobulin (Ig) A stood out due to its potent release associated with a more severe clinical form.

Conclusions

It is concluded that through this study it is possible to have a brief overview of the main immunological biomarkers and their function during SARS-CoV-2 infection in particular cell types. In critically ill individuals, adaptive immunity is varied, aberrantly compromised, and late. In particular, the T-cell response is also an essential and necessary component in immunological memory and therefore should be addressed in vaccine formulation strategies.

Time evolution of cytokine profiles associated with mortality in COVID-19 hospitalized patients

Background

High cytokine levels have been associated with severe COVID-19 disease. Although many cytokine studies have been performed, not many of them include combinatorial analysis of cytokine profiles through time. In this study we investigate the association of certain cytokine profiles and its evolution, and mortality in SARS-CoV2 infection in hospitalized patients.

Methods

Serum concentration of 45 cytokines was determined in 28 controls at day of admission and in 108 patients with COVID-19 disease at first, third and sixth day of admission. A principal component analysis (PCA) was performed to characterize cytokine profiles through time associated with mortality and survival in hospitalized patients.

Results

At day of admission non-survivors present significantly higher levels of IL-1α and VEGFA (PC3) but not through follow up. However, the combination of HGF, MCP-1, IL-18, eotaxine, and SCF (PC2) are significantly higher in non-survivors at all three time-points presenting an increased trend in this group through time. On the other hand, BDNF, IL-12 and IL-15 (PC1) are significantly reduced in non-survivors at all time points with a decreasing trend through time, though a protective factor. The combined mortality prediction accuracy of PC3 at day 1 and PC1 and PC2 at day 6 is 89.00% (p<0.001).

Conclusions

Hypercytokinemia is a hallmark of COVID-19 but relevant differences between survivors and non-survivors can be early observed. Combinatorial analysis of serum cytokines and chemokines can contribute to mortality risk assessment and optimize therapeutic strategies. Three clusters of cytokines have been identified as independent markers or risk factors of COVID mortality.

Immunological investigation of a multiepitope peptide vaccine candidate based on main proteins of SARS-CoV-2 pathogen

Multiepitope vaccines could induce multiantigenic immunity against large complex pathogens with different strain variants. Herein, the in silico, in vitro and in vivo studies were used to design and develop a novel candidate antigenic multiepitope vaccine against SARS-CoV-2 pathogen. The designed multiepitope construct targets the spike glycoprotein (S), membrane protein (M), and nucleocapsid phosphoprotein (N) of SARS-CoV-2 (i.e., the S-N-M construct). This construct contains the cytotoxic T lymphocyte (CTL)-, helper T lymphocyte (HTL)-, and linear B lymphocyte (LBL)-inducing epitopes. The multiepitope s-n-m fusion gene was subcloned in prokaryotic (pET24a) and eukaryotic (pcDNA3.1) expression vectors. Its expression was evaluated in mammalian cell line using LL37 cell penetrating peptide. Moreover, the recombinant multiepitope S-N-M peptide was produced in E. coli strain. Finally, mice were immunized using homologous and heterologous regimens for evaluation of immune responses. Our data indicated that the multiepitope S-N-M peptide construct combined with Montanide 720 in homologous regimen significantly stimulated total IgG, IgG2a, IFN-γ, TNF-α, IL-15, IL-21 and IL-6, and Granzyme B secretion as compared to other groups. Moreover, the pcDNA-s-n-m/ LL37 nanoparticles significantly induced higher immune responses than the naked DNA in both homologous and heterologous regimens. In general, our designed multiepitope vaccine construct can be considered as a vaccine candidate in SARS-CoV-2 infection model.

The role of IL-15 on vulvovaginal candidiasis in mice and related adverse pregnancy outcomes

Vulvovaginal candidiasis (VVC), a major gynecological disease with high recurrence rate, increases the risk of abortion, intrauterine infection, premature rupture of membranes, and premature birth in pregnancy. However, the exact pathogenesis of this disease has yet to be elucidated. To facilitate understanding of the pathogenesis of VVC in pregnancy, this study sought to establish an animal model of vaginal infection with Candida albicans in pregnant mice. Female mice were mated with male mice, and female mice were infected with C. albicans at E4.5 (embryonic day 4.5). The weight and abortion rate of pregnant mice at E0.5, E4.5, E8.5, E11.5, and E18.5 were recorded, respectively, as well as the weights of fetus and placenta on E18.5. Fetal weight at E18.5 and the weight growth rate in the experimental mice was lower than those in the control mice, but the placenta weight at E18.5 and the abortion rate in the experimental mice were increased with those of the control mice. Hematoxylin-eosin (H&E) staining, Gomori-Grocott staining and vaginal lavage culturing were conducted to verify that the experimental mice were infected with C. albicans. Differentially expressed gene IL-15 was screened out by polymerase chain reaction (PCR) array between the two groups. Enzyme-linked immunosorbent assay (ELISA) showed that IL-15 expression in plasma of the mice was decreased in the experimental group compared with the control group. RT-qPCR confirmed that IL-15 mRNA expression was increased in placental tissues, while mRNA expression of IL-15R/JAK1-JAK3/PI3K/PDK1/AKT/P70S6K-mTOR was decreased in placental tissues. In conclusion, this study demonstrated that VVC in BALB/c pregnant mice led to a series of adverse pregnancy outcomes that were related to changes in IL-15 and its downstream signaling pathways, which may indicate a potential therapy for VVC during pregnancy in humans.

Proteomic profiling identifies novel proteins for genetic risk of severe COVID-19: the Atherosclerosis Risk in Communities Study

BACKGROUND

Genome-wide association studies have identified six genetic variants associated with severe COVID-19, yet the mechanisms through which they may affect disease remains unclear. We investigated proteomic signatures related to COVID-19 risk variants rs657152 (ABO), rs10735079 (OAS1/OAS2/OAS3), rs2109069 (DPP9), rs74956615 (TYK2), rs2236757 (IFNAR2) and rs11385942 (SLC6A20/LZTFL1/CCR9/FYCO1/CXCR6/XCR1) as well as their corresponding downstream pathways that may promote severe COVID-19 in risk allele carriers and their potential relevancies to other infection outcomes.

METHODS

A DNA aptamer-based array measured 4870 plasma proteins among 11 471 participants. Linear regression estimated associations between the COVID-19 risk variants and proteins with correction for multiple comparisons, and canonical pathway analysis was conducted. Cox regression assessed associations between proteins identified in the main analysis and risk of incident hospitalized respiratory infections (2570 events) over a 20.7-year follow-up.

RESULTS

The ABO variant rs657152 was associated with 84 proteins in 7241 white participants with 24 replicated in 1671 Black participants. The TYK2 variant rs74956615 was associated with ICAM-1 and -5 in white participants with ICAM-5 replicated in Black participants. Of the 84 proteins identified in the main analysis, seven were significantly associated with incident hospitalized respiratory infections including Ephrin type-A receptor 4 (hazard ratio (HR): 0.87; P = 2.3 × 10-11) and von Willebrand factor type A (HR: 1.17; P = 1.6x10-13).

CONCLUSIONS

Novel proteomics signatures and pathways for COVID-19-related risk variants TYK2 and ABO were identified. A subset of these proteins predicted greater risk of incident hospitalized pneumonia and respiratory infections. Further studies to examine these proteins in COVID-19 patients are warranted.

Opposing roles for sMAdCAM and IL‐15 in COVID‐19 associated cellular immune pathology

Immune cell dysregulation and lymphopenia characterize COVID‐19 pathology in moderate to severe disease. While underlying inflammatory factors have been extensively studied, homeostatic and mucosal migratory signatures remain largely unexplored as causative factors. In this study, we evaluated the association of circulating IL‐6, soluble mucosal addressin cell adhesion molecule (sMAdCAM), and IL‐15 with cellular dysfunction characterizing mild and hypoxemic stages of COVID‐19. A cohort of SARS‐CoV‐2 infected individuals (n = 130) at various stages of disease progression together with healthy controls (n = 16) were recruited from COVID Care Centres (CCCs) across Mumbai, India. Multiparametric flow cytometry was used to perform in‐depth immune subset characterization and to measure plasma IL‐6 levels. sMAdCAM, IL‐15 levels were quantified using ELISA. Distinct depletion profiles, with relative sparing of CD8 effector memory and CD4+ regulatory T cells, were observed in hypoxemic disease within the lymphocyte compartment. An apparent increase in the frequency of intermediate monocytes characterized both mild as well as hypoxemic disease. IL‐6 levels inversely correlated with those of sMAdCAM and both markers showed converse associations with observed lympho‐depletion suggesting opposing roles in pathogenesis. Interestingly, IL‐15, a key cytokine involved in lymphocyte activation and homeostasis, was detected in symptomatic individuals but not in healthy controls or asymptomatic cases. Further, plasma IL‐15 levels negatively correlated with T, B, and NK count suggesting a compensatory production of this cytokine in response to the profound lymphopenia. Finally, higher levels of plasma IL‐15 and IL‐6, but not sMAdCAM, were associated with a longer duration of hospitalization.

Molecular pathways involved in COVID-19 and potential pathway-based therapeutic targets

Deciphering the molecular downstream consequences of severe acute respiratory syndrome coronavirus (SARS-CoV)- 2 infection is important for a greater understanding of the disease and treatment planning. Furthermore, greater understanding of the underlying mechanisms of diagnostic and therapeutic strategies can help in the development of vaccines and drugs against COVID-19. At present, the molecular mechanisms of SARS-CoV-2 in the host cells are not sufficiently comprehended. Some of the mechanisms are proposed considering the existing similarities between SARS-CoV-2 and the other members of the β-CoVs, and others are explained based on studies advanced in the structure and function of SARS-CoV-2. In this review, we endeavored to map the possible mechanisms of the host response following SARS-CoV-2 infection and surveyed current research conducted by in vitro, in vivo and human observations, as well as existing suggestions. We addressed the specific signaling events that can cause cytokine storm and demonstrated three forms of cell death signaling following virus infection, including apoptosis, pyroptosis, and necroptosis. Given the elicited signaling pathways, we introduced possible pathway-based therapeutic targets; ADAM17 was especially highlighted as one of the most important elements of several signaling pathways involved in the immunopathogenesis of COVID-19. We also provided the possible drug candidates against these targets. Moreover, the cytokine-cytokine receptor interaction pathway was found as one of the important cross-talk pathways through a pathway-pathway interaction analysis for SARS-CoV-2 infection.

In Vivo protection from SARS-CoV-2 infection by ATN-161 in k18-hACE2 transgenic mice

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an infectious disease that has spread worldwide. Current treatments are limited in both availability and efficacy, such that improving our understanding of the factors that facilitate infection is urgently needed to more effectively treat infected individuals and to curb the pandemic. We and others have previously demonstrated the significance of interactions between the SARS-CoV-2 spike protein, integrin α5β1, and human ACE2 to facilitate viral entry into host cells in vitro. We previously found that inhibition of integrin α5β1 by the clinically validated small peptide ATN-161 inhibits these spike protein interactions and cell infection in vitro. In continuation with our previous findings, here we have further evaluated the therapeutic potential of ATN-161 on SARS-CoV-2 infection in k18-hACE2 transgenic (SARS-CoV-2 susceptible) mice in vivo. We discovered that treatment with single or repeated intravenous doses of ATN-161 (1 mg/kg) within 48 h after intranasal inoculation with SARS-CoV-2 lead to a reduction of lung viral load, viral immunofluorescence, and improved lung histology in a majority of mice 72 h post-infection. Furthermore, ATN-161 reduced SARS-CoV-2-induced increased expression of lung integrin α5 and αv (an α5-related integrin that has also been implicated in SARS-CoV-2 interactions) as well as the C-X-C motif chemokine ligand 10 (Cxcl10), further supporting the potential involvement of these integrins, and the anti-inflammatory potential of ATN-161, respectively, in SARS-CoV-2 infection. To the best of our knowledge, this is the first study demonstrating the potential therapeutic efficacy of targeting integrin α5β1 in SARS-CoV-2 infection in vivo and supports the development of ATN-161 as a novel SARS-CoV-2 therapy.

Antiviral and Immunomodulatory Effects of Pelargonium sidoides DC. Root Extract EPs® 7630 in SARS-CoV-2-Infected Human Lung Cells

Treatment options for COVID-19 are currently limited. Drugs reducing both viral loads and SARS-CoV-2-induced inflammatory responses would be ideal candidates for COVID-19 therapeutics. Previous in vitro and clinical studies suggest that the proprietary Pelargonium sidoides DC. root extract EPs 7630 has antiviral and immunomodulatory properties, limiting symptom severity and disease duration of infections with several upper respiratory viruses. Here we assessed if EPs 7630 affects SARS-CoV-2 propagation and the innate immune response in the human lung cell line Calu-3. In direct comparison to other highly pathogenic CoV (SARS-CoV, MERS-CoV), SARS-CoV-2 growth was most efficiently inhibited at a non-toxic concentration with an IC50 of 1.61 μg/ml. Particularly, the cellular entry step of SARS-CoV-2 was significantly reduced by EPs 7630 pretreatment (10-100 μg/ml) as shown by spike protein-carrying pseudovirus particles and infectious SARS-CoV-2. Using sequential ultrafiltration, EPs 7630 was separated into fractions containing either prodelphinidins of different oligomerization degrees or small molecule constituents like benzopyranones and purine derivatives. Prodelphinidins with a low oligomerization degree and small molecule constituents were most efficient in inhibiting SARS-CoV-2 entry already at 10 μg/ml and had comparable effects on immune gene regulation as EPs 7630. Downregulation of multiple pro-inflammatory genes (CCL5, IL6, IL1B) was accompanied by upregulation of anti-inflammatory TNFAIP3 at 48 h post-infection. At high concentrations (100 μg/ml) moderately oligomerized prodelphinidins reduced SARS-CoV-2 propagation most efficiently and exhibited pronounced immune gene modulation. Assessment of cytokine secretion in EPs 7630-treated and SARS-CoV-2-coinfected Calu-3 cells showed that pro-inflammatory cytokines IL-1β and IL-6 were elevated whereas multiple other COVID-19-associated cytokines (IL-8, IL-13, TNF-α), chemokines (CXCL9, CXCL10), and growth factors (PDGF, VEGF-A, CD40L) were significantly reduced by EPs 7630. SARS-CoV-2 entry inhibition and the differential immunomodulatory functions of EPs 7630 against SARS-CoV-2 encourage further in vivo studies.

The Combined Use of Cytokine Serum Values with Laboratory Parameters Improves Mortality Prediction of COVID-19 Patients: The Interleukin-15-to-Albumin Ratio

Laboratory parameters display limited accuracy in predicting mortality in coronavirus disease 2019 (COVID-19) patients, as with serum albumin. Emerging evidence suggests that cytokine serum values may enhance the predictive capacity of albumin, especially interleukin (IL)-15. We thus investigated whether the use of the IL-15-to-albumin ratio enables improving mortality prediction at hospital admission in a large group of COVID-19 patients. In this prospective cross-sectional study, we enrolled and followed up three hundred and seventy-eight patients with a COVID-19 diagnosis until hospital discharge or death. Two hundred and fifty-five patients survived, whereas one hundred and twenty-three died. Student’s T-test revealed that non-survivors had a significant two-fold increase in the IL-15-to-albumin ratio compared to survivors (167.3 ± 63.8 versus 74.2 ± 28.5), a difference that was more evident than that found for IL-15 or albumin separately. Likewise, mortality prediction considerably improved when using the IL-15-to-albumin ratio with a cut-off point > 105.4, exhibiting an area under the receiver operating characteristic curve of 0.841 (95% Confidence Interval, 0.725–0.922, p < 0.001). As we outlined here, this is the first study showing that combining IL-15 serum values with albumin improves mortality prediction in COVID-19 patients.

Vaccine efficacy in mutant SARS-CoV-2 variants

Many aspects of the SARS-CoV-2 virus remain poorly understood, including its rapid mutation and its effects on populations of different ages. The present literature of review is focused on the effectiveness of current available vaccines in view of immerging several SARS-CoV-2 variants. The most dangerous and infectious SARS-CoV-2 strain, B117, was recently discovered in the United Kingdom, and another new variant, 501.V2, was discovered in South Africa. In countries such as the United States, Japan, India, and Brazil, the variant B117 spread far more quickly than the original strain. The new SARS-CoV-2 mutations have made producing a universal and effective vaccine more difficult. SARS-CoV-2's S protein, which aids in receptor identification and membrane fusion, is a primary target for vaccine development using its mRNA or inactivated virus. Currently, in the interval of few days new more infectious SARS-CoV-2 mutant is detected, started from SARS-CoV-2 Alpha (B.1.1.7), beta (B.1.351), delta (B.1.617.2), delta plus, gamma (P.1) and now variant lamda. The variant detected first in Peru and spread almost 27 countries including UK that accounts for 82% of new infections. These mutant variants are posing new challenge even to the fully vaccinated individuals and a challenge for the public health. Thus, a need to review current treatment vaccination guideline and strategy as early as possible. Reporting all new SARS-CoV-2 variants and their effectiveness in response to several available vaccines, we would like to draw the attention of health care provider, and all developed countries health care agencies including WHO to frame new guidelines for vaccination and immediate intervention to control the development of new SARS-CoV-2 variants from the third world countries by providing vaccines to the poor countries as early as possible.

Immunotherapy Summary for Cytokine Storm in COVID-19

COVID-19 pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has ravaged the world, resulting in an alarming number of infections and deaths, and the number continues to increase. The pathogenesis caused by the novel coronavirus was found to be a disruption of the pro-inflammatory/anti-inflammatory response. Due to the lack of effective treatments, different strategies and treatment methods are still being researched, with the use of vaccines to make the body immune becoming the most effective means of prevention. Antiviral drugs and respiratory support are often used clinically as needed, but are not yet sufficient to alleviate the cytokine storm (CS) and systemic inflammatory response syndrome. How to neutralize the cytokine storm and inhibit excessive immune cell activation becomes the key to treating neocoronavirus pneumonia. Immunotherapy through the application of hormones and monoclonal antibodies can alleviate the immune imbalance, but the clinical effectiveness and side effects remain controversial. This article reviews the pathogenesis of neocoronavirus pneumonia and discusses the immunomodulatory therapies currently applied to COVID-19. We aim to give some conceptual thought to the prevention and immunotherapy of neocoronavirus pneumonia.

The Relation of the Viral Structure of SARS-CoV2, High-Risk Condition, and Plasma Levels of IL-4, IL-10, and IL-15 in COVID-19 Patients compared to SARS and MERS Infections

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) has high mortality due to the widespread infection and the strong immune system reaction. Interleukins (ILs) are among the main immune factors contributing to the deterioration of the immune response and the formation of cytokine storms in coronavirus disease 2019 (COVID-19) infections.

INTRODUCTION

This review article investigated the relationship between virus structure, risk factors, and patient plasma interleukin levels in infections caused by the coronavirus family.

METHOD

The keywords "interleukin," "coronavirus structure," "plasma," and "risk factors" were the main words searched to find a relationship among different interleukins, coronavirus structures, and risk factors in ISI, PUBMED, SCOPUS, and Google Scholar databases.

RESULT

Patients with high-risk conditions with independent panels of immune system markers are more susceptible to death caused by SARS-CoV2. IL-4, IL-10, and IL-15 are probably secreted at different levels in patients with coronavirus infections despite the similarity of inflammatory markers during coronavirus infections. SARS-CoV2 and SARS-CoV increase the secretion of IL-4 in the Middle East respiratory syndrome coronavirus (MERS-CoV) infection, while it remains unchanged in MERS-CoV infection. MERS-CoV infection demonstrates increased IL-10 levels. However, IL-10 levels increase during SARS-CoV infection, and different levels are recorded in SARS-CoV2. MERS-CoV increases IL-15 secretion while its levels remain unchanged in SARS-CoV2.

CONCLUSION

In conclusion, the different structures of SARS-CoV2, such as length of spike or nonstructural proteins (NSPs), and susceptibility of patients based on their risk factors may lead to differences in immune marker secretion and pathogenicity. Therefore, identifying and controlling interleukin levels can play a significant role in controlling the symptoms and the development of individual-specific treatments.

Risk factors for disease severity in COVID-19 patients: A single-center retrospective study

Background

The outbreak of coronavirus disease 2019 (COVID-19) has posed a huge threat to human health. However, little is known regarding the risk factors associated with COVID-19 severity. We aimed to explore early-stage disease risk factors associated with eventual disease severity.

Methods

This study enrolled 486 hospitalized, non-intensive care unit (ICU)-admitted adult patients with COVID-19 (age ≥ 18 years) treated at Wuhan Jinyintan Hospital, who were divided into three groups according to disease severity. The demographic, clinical, and laboratory data at admission and clinical outcomes were compared among severity groups, and the risk factors for disease severity were identified by multiple regression analysis.

Results

Of 486 patients with COVID-19, 405 (83.33%) were discharged, 33 (6.71%) died outside of the ICU, and 48 (7.20%) were still being treated in the ICU by the time the study period ended. Significant differences in age, lymphocyte counts, and the levels of procalcitonin, aspartate aminotransferase, and D-dimer (P < 0.001 for all) among the three groups. Further analysis showed that older age, decreased lymphocyte counts, and increased procalcitonin, aspartate aminotransferase, and D-dimer levels were significantly associated with disease progression.

Conclusion

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may impair the immune system, the blood coagulation system, and hepatic and cardiac function. Some clinical characteristics and laboratory findings can help identify patients with a high risk of disease severity, which can be significant for appropriate resource allocation during the COVID-19 pandemic.

Interleukin-21 in Viral Infections

Interleukin (IL)-21 is a cytokine that affects the differentiation and function of lymphoid and myeloid cells and regulates both innate and adaptive immune responses. In addition to regulating the immune response to tumor and viral infections, IL-21 also has a profound effect on the development of autoimmune and inflammatory diseases. IL-21 is produced mainly from CD4⁺ T cells-in particular, follicular helper T (Tfh) cells-which have a great influence on the regulation of antibody production. It is also an important cytokine for the activation of CD8⁺ T cells, and its role in recovering the function of CD8⁺ T cells exhausted by chronic microbial infections and cancer has been clarified. Thus, IL-21 plays an extremely important role in viral infections, especially chronic viral infections. In this review, I will introduce the findings to date on how IL-21 is involved in some typical viral infections and the potential of treating viral diseases with IL-21.

Unbiased Analysis of Temporal Changes in Immune Serum Markers in Acute COVID-19 Infection With Emphasis on Organ Failure, Anti-Viral Treatment, and Demographic Characteristics

Identification of novel immune biomarkers to gauge the underlying pathology and severity of COVID-19 has been difficult due to the lack of longitudinal studies. Here, we analyzed serum collected upon COVID-19 admission (t1), 48 hours (t2), and seven days later (t3) using Olink proteomics and correlated to clinical, demographics, and therapeutic data. Older age positively correlated with decorin, pleiotrophin, and TNFRS21 but inversely correlated with chemokine (both C-C and C-X-C type) ligands, monocyte attractant proteins (MCP) and TNFRS14. The burden of pre-existing conditions was positively correlated with MCP-4, CAIX, TWEAK, TNFRS12A, and PD-L2 levels. Individuals with COVID-19 demonstrated increased expression of several chemokines, most notably from the C-C and C-X-C family, as well as MCP-1 and MCP-3 early in the course of the disease. Similarly, deceased individuals had elevated MCP-1 and MCP-3 as well as Gal-9 serum levels. LAMP3, GZMB, and LAG3 at admission correlated with mortality. Only CX3CL13 and MCP-4 correlated positively with APACHE score and length of stay, while decorin, MUC-16 and TNFRSF21 with being admitted to the ICU. We also identified several organ-failure-specific immunological markers, including those for respiratory (IL-18, IL-15, Gal-9) or kidney failure (CD28, VEGF). Treatment with hydroxychloroquine, remdesivir, convalescent plasma, and steroids had a very limited effect on the serum variation of biomarkers. Our study identified several potential targets related to COVID-19 heterogeneity (MCP-1, MCP-3, MCP-4, TNFR superfamily members, and programmed death-ligand), suggesting a potential role of these molecules in the pathology of COVID-19.

SARS-CoV-2 mediated neuroinflammation and the impact of COVID-19 in neurological disorders

SARS-CoV-2 is a novel coronavirus that severely affects the respiratory system, is the cause of the COVID-19 pandemic, and is projected to result in the deaths of 2 million people worldwide. Recent reports suggest that SARS-CoV-2 also affects the central nervous system along with other organs. COVID-19-associated complications are observed in older people with underlying neurological conditions like stroke, Alzheimer's disease, and Parkinson's disease. Hence, we discuss SARS-CoV-2 viral replication and its inflammation-mediated infection. This review also focuses on COVID-19 associated neurological complications in individuals with those complications as well as other groups of people. Finally, we also briefly discuss the current therapies available to treat patients, as well as ongoing available treatments and vaccines for effective cures with a special focus on the therapeutic potential of a small 5 amino acid peptide (PHSCN), ATN-161, that inhibits SARS-CoV-2 spike protein binding to both integrin α5β1 and α5β1/hACE2.

An immune-based biomarker signature is associated with mortality in COVID-19 patients

Immune and inflammatory responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contribute to disease severity of coronavirus disease 2019 (COVID-19). However, the utility of specific immune-based biomarkers to predict clinical outcome remains elusive. Here, we analyzed levels of 66 soluble biomarkers in 175 Italian patients with COVID-19 ranging from mild/moderate to critical severity and assessed type I IFN-, type II IFN-, and NF-κB-dependent whole-blood transcriptional signatures. A broad inflammatory signature was observed, implicating activation of various immune and nonhematopoietic cell subsets. Discordance between IFN-α2a protein and IFNA2 transcript levels in blood suggests that type I IFNs during COVID-19 may be primarily produced by tissue-resident cells. Multivariable analysis of patients' first samples revealed 12 biomarkers (CCL2, IL-15, soluble ST2 [sST2], NGAL, sTNFRSF1A, ferritin, IL-6, S100A9, MMP-9, IL-2, sVEGFR1, IL-10) that when increased were independently associated with mortality. Multivariate analyses of longitudinal biomarker trajectories identified 8 of the aforementioned biomarkers (IL-15, IL-2, NGAL, CCL2, MMP-9, sTNFRSF1A, sST2, IL-10) and 2 additional biomarkers (lactoferrin, CXCL9) that were substantially associated with mortality when increased, while IL-1α was associated with mortality when decreased. Among these, sST2, sTNFRSF1A, IL-10, and IL-15 were consistently higher throughout the hospitalization in patients who died versus those who recovered, suggesting that these biomarkers may provide an early warning of eventual disease outcome.

Recent findings on the Coronavirus disease 2019 (COVID-19); immunopathogenesis and immunotherapeutics

Severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) is responsible for recent ongoing public health emergency in the world. Sharing structural and behavioral similarities with its ancestors [SARS and Middle East Respiratory Syndrome (MERS)], SARS-CoV-2 has lower fatality but faster transmission. We have gone through a long path to recognize SARS and MERS, therefore our knowledge regarding SARS-CoV-2 is not raw. Various responses of the immune system account for the wide spectrum of clinical manifestations in Coronavirus disease-2019 (COVID-19). Given the innate immune response as the front line of defense, it is immediately activated after the virus entry. Consequently, adaptive immune response is activated to eradicate the virus. However, this does not occur in every case and immune response is the main culprit causing the pathological manifestations of COVID-19. Lethal forms of the disease are correlated with inefficient and/or insufficient immune responses associated with cytokine storm. Current therapeutic approach for COVID-19 is in favor of suppressing extreme inflammatory responses, while maintaining the immune system alert and responsive against the virus. This could be contributing along with administration of antiviral drugs in such patients. Furthermore, supplementation with different compounds, such as vitamin D, has been tested to modulate the immune system responses. A thorough understanding of chronological events in COVID-19 contributing to the development of a highly efficient treatment has not figured out yet. This review focuses on the virus-immune system interaction as well as currently available and potential therapeutic approaches targeting immune system in the treatment of COVID-19 patients.

Cancerona: Challenges of Cancer Management in Times of COVID-19 Pandemic

Coronavirus disease 2019 (COVID-19) has infected millions of people worldwide and emerged to be the biggest global health threat claiming hundreds of thousands of lives at exponential rates. The severity of the disease increases with old age and presence of underlying health conditions, such as cancer. Managing cancer patients under these circumstances is rather challenging, given their compromised immunity and the overwhelmed health care services by COVID-19 community transmission. Thus, it is prudent to establish common guidelines for the monitoring and treatment of cancer patients. In this review, we comprehensively investigate the various aspects of cancer care during the COVID-19 pandemic, discuss challenges faced while treating cancer patients, and propose potential approaches to manage COVID-19 among this vulnerable population. We also discuss molecular aberrations and genetic changes associated with cancer and their role in affecting the virus' infectivity and severity. Lastly, we shed light on therapeutic approaches that can encompass both diseases without compromising one over the other.

Immunomodulatory Therapeutic Proteins in COVID-19: Current Clinical Development and Clinical Pharmacology Considerations

The coronavirus disease 2019 (COVID‐19) pandemic caused by infection with SARS‐CoV‐2 has led to more than 600 000 deaths worldwide. Patients with severe disease often experience acute respiratory distress characterized by upregulation of multiple cytokines. Immunomodulatory biological therapies are being evaluated in clinical trials for the management of the systemic inflammatory response and pulmonary complications in patients with advanced stages of COVID‐19. In this review, we summarize the clinical pharmacology considerations in the development of immunomodulatory therapeutic proteins for mitigating the heightened inflammatory response identified in COVID‐19.