Immune-checkpoint inhibitors from cancer to COVID‑19: A promising avenue for the treatment of patients with COVID‑19 (Review)

The implication of targeting PD-1:PD-L1 pathway in treating sepsis through immunostimulatory and anti-inflammatory pathways

Sepsis currently remains a major contributor to mortality in the intensive care unit (ICU), with 48.9 million cases reported globally and a mortality rate of 22.5% in 2017, accounting for almost 20% of all-cause mortality worldwide. This highlights the urgent need to improve the understanding and treatment of this condition. Sepsis is now recognized as a dysregulation of the host immune response to infection, characterized by an excessive inflammatory response and immune paralysis. This dysregulation leads to secondary infections, multiple organ dysfunction syndrome (MODS), and ultimately death. PD-L1, a co-inhibitory molecule expressed in immune cells, has emerged as a critical factor in sepsis. Numerous studies have found a significant association between the expression of PD-1/PD-L1 and sepsis, with a particular focus on PD-L1 expressed on neutrophils recently. This review explores the role of PD-1/PD-L1 in immunostimulatory and anti-inflammatory pathways, illustrates the intricate link between PD-1/PD-L1 and sepsis, and summarizes current therapeutic approaches against PD-1/PD-L1 in the treatment and prognosis of sepsis in preclinical and clinical studies.

Analytical approaches for determination of COVID-19 candidate drugs in human biological matrices

Since the outbreak of the COVID-19 pandemic, the use of antiviral and other available drugs has been considered to combat or reduce the clinical symptoms of patients. In this regard, it would be necessary to choose sensitive and selective analytical techniques for pharmacokinetic and pharmacodynamic studies, monitoring of drug concentration in biological fluids, and determination of the most appropriate dose to achieve the desired effect on the disease. In the present study, the analytical techniques based on spectroscopy and chromatography with different detectors for diagnosis and determination of candidate drugs in the treatment of COVID-19 in human biological fluids are reviewed during the period 2015-2022. Moreover, various sample preparation and extraction techniques, are being used for this purpose, such as protein precipitation (PP), solid-phase extraction (SPE), liquid-liquid extraction (LLE), and QuEChERS (quick, easy, cheap, effective, rugged, and safe) are investigated.

Evaluation of altered miRNA expression pattern to predict COVID-19 severity

Outbreak of COVID-19 pandemic in December 2019 affected millions of people globally. After substantial research, several biomarkers for COVID-19 have been validated however no specific and reliable biomarker for the prognosis of patients with COVID-19 infection exists. Present study was designed to identify specific biomarkers to predict COVID-19 severity and tool for formulating treatment. A small cohort of subjects (n = 43) were enrolled and categorized in four study groups; Dead (n = 16), Severe (n = 10) and Moderate (n = 7) patients and healthy controls (n = 10). Small RNA sequencing was done on Illumina platform after isolation of microRNA from peripheral blood. Differential expression (DE) of miRNA (patients groups compared to control) revealed 118 down-regulated and 103 up-regulated known miRNAs with fold change (FC) expression ≥2 folds and p ≤ 0.05. DE miRNAs were then subjected to functional enrichment and network analysis. Bioinformatic analysis resulted in 31 miRNAs (24 Down-regulated; 7 up-regulated) significantly associated with COVID-19 having AUC>0.8 obtained from ROC curve. Seventeen out of 31 DE miRNAs have been linked to COVID-19 in previous studies. Three miRNAs, hsa-miR-147b-5p and hsa-miR-107 (down-regulated) and hsa-miR-1299 (up-regulated) showed significant unique DE in Dead patients. Another set of 4 miRNAs, hsa-miR-224-5p (down-regulated) and hsa-miR-4659b-3p, hsa-miR-495-3p and hsa-miR-335-3p were differentially up-regulated uniquely in Severe patients. Members of three miRNA families, hsa-miR-20, hsa-miR-32 and hsa-miR-548 were significantly down-regulated in all patients group in comparison to healthy controls. Thus a distinct miRNA expression profile was observed in Dead, Severe and Moderate COVID-19 patients. Present study suggests a panel of miRNAs which identified in COVID-19 patients and could be utilized as potential diagnostic biomarkers for predicting COVID-19 severity.

COVID-19 and Thymoquinone: Clinical Benefits, Cure, and Challenges

In today’s world, the outbreak of the coronavirus disease 2019 (COVID-19) has spread throughout the world, causing severe acute respiratory syndrome (SARS) and several associated complications in various organs (heart, liver, kidney, and gastrointestinal tract), as well as significant multiple organ dysfunction, shock, and even death. In order to overcome the serious complications associated with this pandemic virus and to prevent SARS-CoV-2 entry into the host cell, it is necessary to repurpose currently available drugs with a broad medicinal application as soon as they become available. There are several therapeutics under investigation for improving the overall prognosis of COVID-19 patients, but none of them has demonstrated clinical efficacy to date, which is disappointing. It is in this pattern that Nigella sativa seeds manifest their extensive therapeutic effects, which have been reported to be particularly effective in the treatment of skin diseases, jaundice, and gastrointestinal problems. One important component of these seeds is thymoquinone (TQ), which has a wide range of beneficial properties, including antioxidant and anti-inflammatory properties, as well as antibacterial and parasitic properties, in addition to anticarcinogenic, antiallergic, and antiviral properties. This comprehensive review discussed the possibility of an emerging natural drug with a wide range of medical applications; the use of TQ to overcome the complications of COVID-19 infection; and the challenges that are impeding the commercialization of this promising phytochemical compound. TQ is recommended as a highly effective weapon in the fight against the novel coronavirus because of its dual antiviral action, in addition to its capacity to lessen the possibility of SARS-CoV-2 penetration into cells. However, future clinical trials are required to confirm the role of TQ in overcoming the complications of COVID-19 infection.

Agonistic and antagonistic targeting of immune checkpoint molecules differentially regulate osteoclastogenesis

Introduction

Immune checkpoint inhibitors are used in the treatment of various cancers and have been extensively researched with regard to inflammatory and autoimmune diseases. However, this revolutionary therapeutic strategy often provokes critical auto-inflammatory adverse events, such as inflammatory reactions affecting the cardiovascular, gastrointestinal, nervous, and skeletal systems. Because the function of these immunomodulatory co-receptors is highly cell-type specific and the role of macrophages as osteoclast precursors is widely published, we aimed to analyze the effect of immune checkpoint inhibitors on these bone-resorbing cells.

Methods

We established an in vitro model of osteoclastogenesis using human peripheral blood mononuclear cells, to which various immune checkpoints and corresponding antagonistic antibodies were administered. Formation of osteoclasts was quantified and cell morphology was analyzed via immunofluorescence staining, cell size measurements, and calculation of cell numbers in a multitude of samples.

Results

These methodical approaches for osteoclast research achieved objective, comparable, and reproducible results despite the great heterogeneity in the form, size, and number of osteoclasts. In addition to the standardization of experimental analyses involving osteoclasts, our study has revealed the substantial effects of agonistic and antagonistic checkpoint modulation on osteoclastogenesis, confirming the importance of immune checkpoints in bone homeostasis.

Discussion

Our work will enable more robust and reproducible investigations into the use of immune checkpoint inhibitors in conditions with diminished bone density such as osteoporosis, aseptic loosening of endoprostheses, cancer, as well as the side effects of cancer therapy, and might even pave the way for novel individualized diagnostic and therapeutic strategies.

Updated Insights into the T Cell-Mediated Immune Response against SARS-CoV-2: A Step towards Efficient and Reliable Vaccines

The emergence of novel variants of SARS-CoV-2 and their abilities to evade the immune response elicited through presently available vaccination makes it essential to recognize the mechanisms through which SARS-CoV-2 interacts with the human immune response. It is essential not only to comprehend the infection mechanism of SARS-CoV-2 but also for the generation of effective and reliable vaccines against COVID-19. The effectiveness of the vaccine is supported by the adaptive immune response, which mainly consists of B and T cells, which play a critical role in deciding the prognosis of the COVID-19 disease. T cells are essential for reducing the viral load and containing the infection. A plethora of viral proteins can be recognized by T cells and provide a broad range of protection, especially amid the emergence of novel variants of SARS-CoV-2. However, the hyperactivation of the effector T cells and reduced number of lymphocytes have been found to be the key characteristics of the severe disease. Notably, excessive T cell activation may cause acute respiratory distress syndrome (ARDS) by producing unwarranted and excessive amounts of cytokines and chemokines. Nevertheless, it is still unknown how T-cell-mediated immune responses function in determining the prognosis of SARS-CoV-2 infection. Additionally, it is unknown how the functional perturbations in the T cells lead to the severe form of the disease and to reduced protection not only against SARS-CoV-2 but many other viral infections. Hence, an updated review has been developed to understand the involvement of T cells in the infection mechanism, which in turn determines the prognosis of the disease. Importantly, we have also focused on the T cells' exhaustion under certain conditions and how these functional perturbations can be modulated for an effective immune response against SARS-CoV-2. Additionally, a range of therapeutic strategies has been discussed that can elevate the T cell-mediated immune response either directly or indirectly.

Proteomic Analysis of Pleural Effusions from COVID-19 Deceased Patients: Enhanced Inflammatory Markers

Critically ill COVID-19 patients with pleural effusion experience longer hospitalization, multisystem inflammatory syndrome, and higher rates of mortality. Generally, pleural effusion can serve as a diagnostic value to differentiate cytokine levels. This study aimed to evaluate the pleural effusions of COVID-19 deceased patients for 182 protein markers. Olink^® Inflammation and Organ Damage panels were used to determine the level of 184 protein markers, e.g., ADA, BTC, CA12, CAPG, CD40, CDCP1, CXCL9, ENTPD2, Flt3L, IL-6, IL-8, LRP1, OSM, PD-L1, PTN, STX8, and VEGFA, which were raised significantly in COVID-19 deceased patients, showing over-stimulation of the immune system and ravaging cytokine storm. The rises of DPP6 and EDIL3 also indicate damage caused to arterial and cardiovascular organs. Overall, this study confirms the elevated levels of CA12, CD40, IL-6, IL-8, PD-L1, and VEGFA, proposing their potential either as biomarkers for the severity and prognosis of the disease or as targets for therapy. Particularly, this study reports upregulated ADA, BTC, DPP6, EDIL3, LIF, ENTPD2, Flt3L, and LRP1 in severe COVID-19 patients for the first time. Pearson's correlation coefficient analysis indicates the involvement of JAK/STAT pathways as a core regulator of hyperinflammation in deceased COVID-19 patients, suggesting the application of JAK inhibitors as a potential efficient treatment.

Programmed Cell Death Protein 1 Axis Inhibition in Viral Infections: Clinical Data and Therapeutic Opportunities

A vital function of the immune system is the modulation of an evolving immune response. It is responsible for guarding against a wide variety of pathogens as well as the establishment of memory responses to some future hostile encounters. Simultaneously, it maintains self-tolerance and minimizes collateral tissue damage at sites of inflammation. In recent years, the regulation of T-cell responses to foreign or self-protein antigens and maintenance of balance between T-cell subsets have been linked to a distinct class of cell surface and extracellular components, the immune checkpoint molecules. The fact that both cancer and viral infections exploit similar, if not the same, immune checkpoint molecules to escape the host immune response highlights the need to study the impact of immune checkpoint blockade on viral infections. More importantly, the process through which immune checkpoint blockade completely changed the way we approach cancer could be the key to decipher the potential role of immunotherapy in the therapeutic algorithm of viral infections. This review focuses on the effect of programmed cell death protein 1/programmed death-ligand 1 blockade on the outcome of viral infections in cancer patients as well as the potential benefit from the incorporation of immune checkpoint inhibitors (ICIs) in treatment of viral infections.

Immune checkpoint alterations and their blockade in COVID-19 patients

Coronavirus disease 2019 (COVID-19) is a highly contagious disease that seriously affects people's lives. Immune dysfunction, which is characterized by abnormal expression of multiple immune checkpoint proteins (ICs) on immune cells, is associated with progression and poor prognosis for tumors and chronic infections. Immunotherapy targeting ICs has been well established in modulating immune function and improving clinical outcome for solid tumors and hematological malignancies. The role of ICs in different populations or COVID-19 stages and the impact of IC blockade remains unclear. In this review, we summarized current studies of alterations in ICs in COVID-19 to better understand immune changes and provide strategies for treating COVID-19 patients, particularly those with cancer.

Increased percentage of apoptotic and CTLA-4 (CD152) expressing cells in CD4+/CD8+ cells in COVID-19 patients

Coronavirus infectious disease 2019 (COVID-19) confirmed cases are characterized by T lymphopenia. Total apoptotic and cytotoxic T-lymphocyte antigen-4 (CTLA-4) expressing cells among CD4+/CD8+ cells were analyzed in 24 COVID-19 patients (16 out-patients and 8 in-patients) and 18 healthy volunteers using flow cytometry to detect their possible role in T lymphopenia. Hospitalized patients did not show significant difference compared to non-hospitalized patients. While the percentage and absolute count of CD4+/CD8+ cells were significantly reduced in COVID-19 cases compared to healthy control (P < .05), the proportion of apoptotic and CTLA-4 expressing CD4+/CD8+ cells were significantly up-regulated in COVID-19 patients (P < .05). In addition, apoptotic and CTLA-4+/CD4+ cells were directly related to dyspnea duration, chest CT score, ferritin, and C-reactive protein and inversely correlated with platelet count in COVID-19 patients. While apoptotic and CTLA-4+/CD8+ cells were directly related to lymphocyte count in COVID-19 patients. The apoptotic and CTLA-4+ cells were directly related to each other in CD4+/CD8+ cells (P < .05). White blood cells (WBCs) (×103/L), eosinophils (ratio and count), lymphocyte ratio, neutrophil ratio, neutrophil/lymphocyte ratio, neutrophil/CD4 ratio, neutrophil/CD8 ratio, CD4+ cells ratio, and CTLA-4+ cells percentage), and CD8+ cells (ratio, count, total apoptotic cell, and CD152 + cells) were all found to be significantly altered in association with COVID-19. Total lymphopenia and depletion of CD4+/CD8+ cells are characterizing COVID-19 patients. Increased apoptosis and CTLA-4 expression in CD4+/CD8+ cells in COVID-19 and their correlations with reduced cell count and severity indicators as CRP and ferritin can be used for diagnosis and follow up of the clinical severity. Our current study proposes promising future diagnostic and therapeutic targets.

"Role of kidney function and concentrations of BAFF, sPD-L1 and sCD25 on mortality in hospitalized patients with COVID-19"

Background

Chronic kidney disease (CKD) is a recognized risk factor for severe complications in COVID-19. Our objective was to analyze the association between kidney function / T and B lymphocyte modulatory factors and risk of mortality in COVID-19 patients.

Methods

In-hospital and 30‐day mortality were analyzed in COVID‐19 patients (n = 110). Plasma levels of selected T and B cell modulators were analyzed and correlated to mortality risk. A subgroup of sex- and eGFR-matched COVID-19 patients was compared to CKD patients without infection and healthy subjects.

Results

COVID-19 patients who died in hospital and within 30 days had significantly higher BAFF and sCD25 plasma levels than survivors. In logistic regression models patients with high BAFF, sCD25 and sPD-L1 levels had significantly higher risk of both in-hospital and 30-day mortality while there was no association to eGFR. In the subgroup analysis, a higher level of BAFF, IFN-α, sCD25, sPD-L1 and a lower level of sCD40L was observed in COVID-19 patients compared to the CKD group with corresponding kidney function.

Conclusions

We demonstrate that kidney function and concentrations of BAFF, sCD25 and PD-L1, independent of previously recognized risk factors; age, male gender, and leukocytosis are associated with risk of in-hospital and 30-day mortality in patients with COVID-19. These data indicate the significance of adaptive immune system modulators in COVID-19 and motivate further analysis to identify new potential prognostic and therapeutic approaches.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02924-2.

COVID-19 Outcomes in Stage IV Cancer Patients Receiving Immune Checkpoint Inhibitors

Cancer patients are a vulnerable population in the current coronavirus disease 2019 (COVID-19) outbreak. The impact of immune checkpoint inhibitors (ICIs) on the outcomes of COVID-19 infection in cancer patients remains largely unclear. We retrospectively investigated all solid cancer patients who received at least one cycle of ICIs at a single institution between August 2020 and August 2021. All stage IV solid cancer patients who were on or ceased ICI treatment when diagnosed with COVID-19 were eligible. All COVID-19 infections were confirmed by RT-PCR. Risk factors for hospitalization, severe symptoms, and death were analyzed. A total of 56 patients were included in our study. Twenty (35.7%) patients require hospitalization, 12 (21.4%) developed severe symptoms, and 10 (17.9%) died from COVID-19 infection. ICI treatment was interrupted in 37 patients (66.1%), 24 of whom (64.9%) had treatment resumed. Eight (80%) COVID-19-related death occurred in unvaccinated individuals. Reinfection occurred in seven patients (12.5%), and three of them died from their second COVID-19 infection. Factors associated with hospitalization were high Charlson comorbidity score (OR 1.56, 95% CI 1.10–2.23, p = 0.01) and lymphocyte ≤ 1500 mm³ (OR 10.05, 95% CI 2.03–49.85, p = 0.005). Age, chemoimmunotherapy, and ICI treatment duration were not associated with increased risk of hospitalization, severe symptoms, or COVID-19-related mortality. ICI therapy does not impose an increased risk for severe COVID-19 infection in stage IV cancer patients. Vaccination should be encouraged among this population. Clinicians should be cognizant of a potential worse outcome in COVID-19-reinfected patients.

Global research trends on the links between gut microbiota and cancer immunotherapy: A bibliometric analysis (2012-2021)

Background

There is a crosstalk between gut microbiota (GM) and cancer immunotherapy (CI). The purpose of this study is to use bibliometric analysis to identify the highly cited papers relating to GM/CI and explore the research status and development trends of the GM/CI research.

Methods

A literature search regarding GM/CI publications from 2012 to 2021 was undertaken on July 4, 2022. The article titles, journals, authors, institutions, countries, total citations, keywords, and other information were extracted from the Science Citation Index Expanded (SCIE) of Web of Science Core Collection (WoSCC). The Bibliometrix of R package and VOSviewer were used for bibliometric analysis.

Results

A total of 665 papers were extracted. The number of papers has increased rapidly over the past decade, especially after 2018. The United States and China had the most publications and made great contributions to this field. Th5e Univ Texas MD Anderson Canc Ctr and Univ Paris Saclay were absolutely in the leading position in GM/CI. The most influential authors were Zitvogel L and Routy B. Frontiers in Immunology had the most publications and Science had the most total citations. Historical direct citation analysis explained the historical evolution in GM/CI. Highly cited papers and high-frequency keywords illustrated the current status and trends of GM/CI. Four clusters were identified and the important topics included the role of GM and antibiotics in CI, the methods of targeting GM to improve CI outcomes, the mechanism by which GM affects CI and the application of ICIs in melanoma. “Tumor microbiome”, “proton pump inhibitors” and “prognosis” may be the new focus of attention in the next few years.

Conclusion

This study filtered global publications on GM/CI correlation and analyzed their bibliometric characteristics, identified the most cited papers in GM/CI, and gained insight into the status, hotspots and trends of global GM/CI research, which may inform researchers and practitioners of future directions.

Liquid Biopsy and Circulating Biomarkers for the Diagnosis of Precancerous and Cancerous Oral Lesions

Oral cancer is one of the most common malignancies worldwide, accounting for 2% of all cases annually and 1.8% of all cancer deaths. To date, tissue biopsy and histopathological analyses are the gold standard methods for the diagnosis of oral cancers. However, oral cancer is generally diagnosed at advanced stages with a consequent poor 5-year survival (~50%) due to limited screening programs and inefficient physical examination strategies. To address these limitations, liquid biopsy is recently emerging as a novel minimally invasive tool for the early identification of tumors as well as for the evaluation of tumor heterogeneity and prognosis of patients. Several studies have demonstrated that liquid biopsy in oral cancer could be useful for the detection of circulating biomarkers including circulating tumor DNA (ctDNA), microRNAs (miRNAs), proteins, and exosomes, thus improving diagnostic strategies and paving the way to personalized medicine. However, the application of liquid biopsy in oral cancer is still limited and further studies are needed to better clarify its clinical impact. The present manuscript aims to provide an updated overview of the potential use of liquid biopsy as an additional tool for the management of oral lesions by describing the available methodologies and the most promising biomarkers.

Clinical course of COVID-19 infection in a melanoma patient treated with nivolumab and bempegaldesleukin: a case report

The exact impact of immune checkpoint inhibitors in the course and outcome of COVID-19 in cancer patients is currently unclear. Herein, we present the first description of an elderly melanoma patient who developed COVID-19 pneumonia while under treatment with nivolumab and bempegaldesleukin in combination with an investigational PEGylated interleukin (IL-2). We present the clinical characteristics and the laboratory and imaging findings of our patient during the course of COVID-19 pneumonia. Moreover, we discuss the currently available data regarding the mechanism of action of immune checkpoint inhibitors and IL-2 analogs in the treatment of COVID-19. The administration of these agents did not have a negative effect on the outcome of COVID-19 pneumonia in an elderly melanoma patient.

Immune checkpoint inhibitors represent a major advance in the treatment of several solid malignancies, including melanoma. Bempegaldesleukin is an investigational PEGylated IL-2 that is being evaluated, in combination with nivolumab, in the management of a variety of cancers. The immunomodulation caused by these agents may also modify the immune response in COVID-19. Currently available data regarding the impact of immune checkpoint inhibitors in reducing the severity of COVID-19 in patients with cancer are mixed, whereas no clinical data are available for bempegaldesleukin. Herein, we report the case of an elderly female melanoma patient who developed COVID-19 pneumonia while under treatment with nivolumab and bempegaldesleukin. The administration of these agents did not have a negative effect on the outcome of COVID-19 pneumonia in our patient.

Beyond GWAS-Could Genetic Differentiation within the Allograft Rejection Pathway Shape Natural Immunity to COVID-19?

COVID-19 infections pose a serious global health concern so it is crucial to identify the biomarkers for the susceptibility to and resistance against this disease that could help in a rapid risk assessment and reliable decisions being made on patients' treatment and their potential hospitalisation. Several studies investigated the factors associated with severe COVID-19 outcomes that can be either environmental, population based, or genetic. It was demonstrated that the genetics of the host plays an important role in the various immune responses and, therefore, there are different clinical presentations of COVID-19 infection. In this study, we aimed to use variant descriptive statistics from GWAS (Genome-Wide Association Study) and variant genomic annotations to identify metabolic pathways that are associated with a severe COVID-19 infection as well as pathways related to resistance to COVID-19. For this purpose, we applied a custom-designed mixed linear model implemented into custom-written software. Our analysis of more than 12.5 million SNPs did not indicate any pathway that was significant for a severe COVID-19 infection. However, the Allograft rejection pathway (hsa05330) was significant (p = 0.01087) for resistance to the infection. The majority of the 27 SNP marking genes constituting the Allograft rejection pathway were located on chromosome 6 (19 SNPs) and the remainder were mapped to chromosomes 2, 3, 10, 12, 20, and X. This pathway comprises several immune system components crucial for the self versus non-self recognition, but also the components of antiviral immunity. Our study demonstrated that not only single variants are important for resistance to COVID-19, but also the cumulative impact of several SNPs within the same pathway matters.

A comprehensive review about immune responses and exhaustion during coronavirus disease (COVID-19)

Coronavirus disease (COVID-19) is a viral infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. The infection was reported in Wuhan, China, in late December 2019 and has become a major global concern due to severe respiratory infections and high transmission rates. Evidence suggests that the strong interaction between SARS-CoV-2 and patients' immune systems leads to various clinical symptoms of COVID-19. Although the adaptive immune responses are essential for eliminating SARS-CoV-2, the innate immune system may, in some cases, cause the infection to progress. The cytotoxic CD8+ T cells in adaptive immune responses demonstrated functional exhaustion through upregulation of exhaustion markers. In this regard, humoral immune responses play an essential role in combat SARS-CoV-2 because SARS-CoV-2 restricts antigen presentation through downregulation of MHC class I and II molecules that lead to the inhibition of T cell-mediated immune response responses. This review summarizes the exact pathogenesis of SARS-CoV-2 and the alteration of the immune response during SARS-CoV-2 infection. In addition, we've explained the exhaustion of the immune system during SARS-CoV-2 and the potential immunomodulation approach to overcome this phenomenon. Video Abstract.

Modeling recapitulates the heterogeneous outcomes of SARS-CoV-2 infection and quantifies the differences in the innate immune and CD8 T-cell responses between patients experiencing mild and severe symptoms

SARS-CoV-2 infection results in highly heterogeneous outcomes, from cure without symptoms to acute respiratory distress and death. Empirical evidence points to the prominent roles of innate immune and CD8 T-cell responses in determining the outcomes. However, how these immune arms act in concert to elicit the outcomes remains unclear. Here, we developed a mathematical model of within-host SARS-CoV-2 infection that incorporates the essential features of the innate immune and CD8 T-cell responses. Remarkably, by varying the strengths and timings of the two immune arms, the model recapitulated the entire spectrum of outcomes realized. Furthermore, model predictions offered plausible explanations of several confounding clinical observations, including the occurrence of multiple peaks in viral load, viral recrudescence after symptom loss, and prolonged viral positivity. We applied the model to analyze published datasets of longitudinal viral load measurements from patients exhibiting diverse outcomes. The model provided excellent fits to the data. The best-fit parameter estimates indicated a nearly 80-fold stronger innate immune response and an over 200-fold more sensitive CD8 T-cell response in patients with mild compared to severe infection. These estimates provide quantitative insights into the likely origins of the dramatic inter-patient variability in the outcomes of SARS-CoV-2 infection. The insights have implications for interventions aimed at preventing severe disease and for understanding the differences between viral variants.

COVID-19 immunotherapy: Treatment based on the immune cell-mediated approaches

Multiple efforts are currently underway to control and treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19) worldwide. Despite all efforts, the virus that emerged in Wuhan city has rapidly spread globally and led to a public health emergency of international concern (PHEIC) due to the lack of approved antiviral therapy. Nevertheless, SARS-CoV-2 has had a significant influence on the evolution of cellular therapeutic approaches. Adoptive immune cell therapy is innovative and offers either promising prophylactic or therapy for patients with moderate-to-severe COVID-19. This approach is aimed at developing safety and providing secure and effective therapy in combination with standard therapy for all COVID-19 infected individuals. Based on the effective results of previous studies on both inflammatory and autoimmune diseases, various immune cell therapies against COVID-19 have been reviewed and discussed. It must be considered that the application of cell therapy for treatment and to eliminate infected respiratory cells could result in excessive inflammation, so this treatment must be used in combination with other treatments, despite its many beneficial efforts.

COVID-19 and Preexisting Comorbidities: Risks, Synergies, and Clinical Outcomes

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated symptoms, named coronavirus disease 2019 (COVID-19), have rapidly spread worldwide, resulting in the declaration of a pandemic. When several countries began enacting quarantine and lockdown policies, the pandemic as it is now known truly began. While most patients have minimal symptoms, approximately 20% of verified subjects are suffering from serious medical consequences. Co-existing diseases, such as cardiovascular disease, cancer, diabetes, and others, have been shown to make patients more vulnerable to severe outcomes from COVID-19 by modulating host-viral interactions and immune responses, causing severe infection and mortality. In this review, we outline the putative signaling pathways at the interface of COVID-19 and several diseases, emphasizing the clinical and molecular implications of concurring diseases in COVID-19 clinical outcomes. As evidence is limited on co-existing diseases and COVID-19, most findings are preliminary, and further research is required for optimal management of patients with comorbidities.

The Role of Immune Checkpoint Molecules on Macrophages in Cancer, Infection, and Autoimmune Pathologies

Immune checkpoint inhibitors have revolutionized immunotherapy against various cancers over the last decade. The use of checkpoint inhibitors results in remarkable re-activation of patients’ immune system, but is also associated with significant adverse events. In this review, we emphasize the importance of cell-type specificity in the context of immune checkpoint-based interventions and particularly focus on the relevance of macrophages. Immune checkpoint blockade alters the dynamic macrophage phenotypes and thereby substantially manipulates therapeutical outcome. Considering the macrophage-specific immune checkpoint biology, it seems feasible to ameliorate the situation of patients with severe side effects and even increase the probability of survival for non-responders to checkpoint inhibition. Apart from malignancies, investigating immune checkpoint molecules on macrophages has stimulated their fundamental characterization and use in other diseases as well, such as acute and chronic infections and autoimmune pathologies. Although the macrophage-specific effect of checkpoint molecules has been less studied so far, the current literature shows that a macrophage-centered blockade of immune checkpoints as well as a stimulation of their expression represents promising therapeutic avenues. Ultimately, the therapeutic potential of a macrophage-focused checkpoint therapy might be maximized by diagnostically assessing individual checkpoint expression levels on macrophages, thereby personalizing an effective treatment approach for each patient having cancer, infection, or autoimmune diseases.

CD8+ T Cells in SARS-CoV-2 Induced Disease and Cancer-Clinical Perspectives

Dysregulated innate and adaptive immunity is a sign of SARS-CoV-2-induced disease and cancer. CD8+ T cells are important cells of the immune system. The cells belong to the adaptive immunity and take a front-line defense against viral infections and cancer. Extreme CD8+ T-cell activities in the lung of patients with a SARS-CoV-2-induced disease and within the tumor microenvironment (TME) will change their functionality into exhausted state and undergo apoptosis. Such diminished immunity will put cancer cases at a high-risk group for SARS-CoV-2-induced disease, rendering viral sepsis and a more severe condition which will finally cause a higher rate of mortality. Recovering responses from CD8+ T cells is a purpose of vaccination against SARS-CoV-2. The aim of this review is to discuss the CD8+ T cellular state in SARS-CoV-2-induced disease and in cancer and to present some strategies for recovering the functionality of these critical cells.

Clinical, radiological, and pathological findings in patients with persistent lung disease following SARS-CoV-2 infection

Some patients experience pulmonary sequelae after SARS-CoV-2 infection, ranging from self-limited abnormalities to major lung diseases. Morphological analysis of lung tissue may help our understanding of pathogenic mechanisms and help to provide consistent personalised management. The aim of this study was to ascertain morphological and immunomolecular features of lung tissue. Transbronchial lung cryobiopsy was carried out in patients with persistent symptoms and computed tomography suggestive of residual lung disease after recovery from SARS-CoV-2 infection. 164 patients were referred for suspected pulmonary sequelae after COVID-19; 10 patients with >5% parenchymal lung disease underwent lung biopsy. The histological pattern of lung disease was not homogeneous and three different case clusters could be identified, which was mirrored by their clinical and radiological features. Cluster 1 (“chronic fibrosing”) was characterised by post-infection progression of pre-existing interstitial pneumonias. Cluster 2 (“acute/subacute injury”) was characterised by different types and grades of lung injury, ranging from organising pneumonia and fibrosing nonspecific interstitial pneumonia to diffuse alveolar damage. Cluster 3 (“vascular changes”) was characterised by diffuse vascular increase, dilatation and distortion (capillaries and venules) within otherwise normal parenchyma. Clusters 2 and 3 had immunophenotypical changes similar to those observed in early/mild COVID-19 pneumonias (abnormal expression of STAT3 in hyperplastic pneumocytes and PD-L1, IDO and STAT3 in endothelial cells). This is the first study correlating histological/immunohistochemical patterns with clinical and radiological pictures of patients with post-COVID lung disease. Different phenotypes with potentially different underlying pathogenic mechanisms have been identified.

Post-COVID lung disease is not a single entity, but includes different subtypes, each of them potentially requiring separate and different managementhttps://bit.ly/3BJDeUF

Immune mechanisms in cancer patients that lead to poor outcomes of SARS-CoV-2 infection

Patients with cancers have been severely affected by the COVID-19 pandemic. This is highlighted by the adverse outcomes in cancer patients with COVID-19 as well as by the impact of the COVID-19 pandemic on cancer care. Patients with cancer constitute a heterogeneous population that exhibits distinct mechanisms of immune dysfunction, associated with distinct systemic features of hot (T-cell-inflamed/infiltrated) and cold (Non-T-cell-inflamed and/or infiltrated) tumors. The former show hyper immune activated cells and a highly inflammatory environment while, contrastingly, the latter show the profile of a senescent and/or quiescent immune system. Thus, the evolution of SARS-CoV-2 infection in different types of cancers can show distinct trajectories which could lead to a variety of clinical and pathophysiological outcomes. The altered immunological environment including cytokines that characterizes hot and cold tumors will lead to different mechanisms of immune dysfunction, which will result in downstream effects on the course of SARS-CoV-2 infection. This review will focus on defining the known contributions of soluble pro- and anti-inflammatory mediators on immune function including altered T-cells and B-cells responses and as well on how these factors modulate the expression of SARS-CoV-2 receptor ACE2, TMPRSS2 expression, and lymph node fibrosis in cancer patients. We will propose immune mechanisms that underlie the distinct courses of SARS-CoV-2 infection in cancer patients and impact on the success of immune based therapies that have significantly improved cancer outcomes. Better understanding of the immune mechanisms prevalent in cancer patients that are associated to the outcomes of SARS-CoV-2 infection will help to identify the high-risk cancer patients and develop immune-based approaches to prevent significant adverse outcomes by targeting these pathways.

Overactivation of IL6 cis‑signaling in leukocytes is an inflammatory hallmark of deep vein thrombosis

Inflammation is a protective response of the body to various injuries, which is strictly regulated by a variety of factors, including immune cells and soluble mediators. However, dysfunction of this defensive mechanism often results in inflammation‑driven diseases, such as deep vein thrombosis (DVT). The complex relationship between inflammatory cell activity and DVT has not been fully elucidated. The present study aimed to investigate the role of interleukin‑6 (IL6) signaling transduction in DVT. To this aim, the expression levels of transmembrane isoforms of the IL6 receptor (IL6R) and the glycoprotein 130 responsible for the IL6 cis‑signaling were evaluated in the peripheral blood mononuclear cells of patients with DVT and of healthy controls. The results indicated that leukocytes from patients with DVT exhibited overexpression of both IL6R and gp130 membrane isoforms and that these were strongly associated with the occurrence of DVT. Overall, the present findings indicated that IL6 cis‑signaling may have a direct involvement in the leukocyte activation in DVT and may serve as a predictive biomarker of DVT development.

Soluble Immune Checkpoints Are Dysregulated in COVID-19 and Heavy Alcohol Users With HIV Infection

Immune checkpoints (ICPs) consist of paired receptor-ligand molecules that exert inhibitory or stimulatory effects on immune defense, surveillance, regulation, and self-tolerance. ICPs exist in both membrane and soluble forms in vivo and in vitro. Imbalances between inhibitory and stimulatory membrane-bound ICPs (mICPs) in malignant cells and immune cells in the tumor immune microenvironment (TIME) have been well documented. Blockades of inhibitory mICPs have emerged as an immense breakthrough in cancer therapeutics. However, the origin, structure, production regulation, and biological significance of soluble ICPs (sICPs) in health and disease largely remains elusive. Soluble ICPs can be generated through either alternative mRNA splicing and secretion or protease-mediated shedding from mICPs. Since sICPs are found in the bloodstream, they likely form a circulating immune regulatory system. In fact, there is increasing evidence that sICPs exhibit biological functions including (1) regulation of antibacterial immunity, (2) interaction with their mICP compartments to positively or negatively regulate immune responses, and (3) competition with their mICP compartments for binding to the ICP blocking antibodies, thereby reducing the efficacy of ICP blockade therapies. Here, we summarize current data of sICPs in cancer and infectious diseases. We particularly focus on sICPs in COVID-19 and HIV infection as they are the two ongoing global pandemics and have created the world's most serious public health challenges. A "storm" of sICPs occurs in the peripheral circulation of COVID-19 patients and is associated with the severity of COVID-19. Similarly, sICPs are highly dysregulated in people living with HIV (PLHIV) and some sICPs remain dysregulated in PLHIV on antiretroviral therapy (ART), indicating these sICPs may serve as biomarkers of incomplete immune reconstitution in PLHIV on ART. We reveal that HIV infection in the setting of alcohol misuse exacerbates sICP dysregulation as PLHIV with heavy alcohol consumption have significantly elevated plasma levels of many sICPs. Thus, both stimulatory and inhibitory sICPs are present in the bloodstream of healthy people and their balance can be disrupted under pathophysiological conditions such as cancer, COVID-19, HIV infection, and alcohol misuse. There is an urgent need to study the role of sICPs in immune regulation in health and disease.

Immunomodulatory Potential of Non-Classical HLA-G in Infections including COVID-19 and Parasitic Diseases

Human Leukocyte Antigen-G (HLA-G), a polymorphic non-classical HLA (HLA-Ib) with immune-regulatory properties in cancers and infectious diseases, presents both membrane-bound and soluble (sHLA-G) isoforms. Polymorphism has implications in host responses to pathogen infections and in pathogenesis. Differential expression patterns of HLA-G/sHLA-G or its polymorphism seem to be related to different pathological conditions, potentially acting as a disease progression biomarker. Pathogen antigens might be involved in the regulation of both membrane-bound and sHLA-G levels and impact immune responses during co-infections. The upregulation of HLA-G in viral and bacterial infections induce tolerance to infection. Recently, sHLA-G was found useful to identify the prognosis of Coronavirus disease 2019 (COVID-19) among patients and it was observed that the high levels of sHLA-G are associated with worse prognosis. The use of pathogens, such as Plasmodium falciparum, as immune modulators for other infections could be extended for the modulation of membrane-bound HLA-G in COVID-19-infected tissues. Overall, such information might open new avenues concerning the effect of some pathogens such as parasites in decreasing the expression level of HLA-G to restrict pathogenesis in some infections or to influence the immune responses after vaccination among others.

N, B. V, S. R, A. S. COVID-19: Invasion, pathogenesis and possible cure - A review

Today, Coronavirus disease (COVID-19) which is believed to be transmitted from bats to humans where the people of Wuhan city, China exposed to the wet animal market is an important international public health anxiety (Xiong et al., 2020). Although, several measures were undertaken to treat the diseases by various medical advancements and by a variety of treatment procedures, still the mortality is higher. Hence, social distancing has been implemented to control the current outburst of this pandemic which spreads through human to human transmission. As a consequence, there is a need to completely understand the route of invasions of the virus into the humans and the target receptors besides the other factors leading to the disease. Several vaccines and drugs have been developed with its own pros and cons. Many are still under the various phase of R&D and clinical trials. Here we highlight the possible entry molecules, pathogenesis, symptomatology, probable cure and the recently developed vaccines for the existing pandemic due to the COVID-19.

Efficacy of the use of mefenamic acid combined with standard medical care vs. standard medical care alone for the treatment of COVID‑19: A randomized double‑blind placebo‑controlled trial

Mefenamic acid is a non‑steroidal anti‑inflammatory drug exhibiting a wide range of anti‑inflammatory, antipyretic, analgesic and probable antiviral activities. The present study evaluated the efficacy of treatment with mefenamic acid combined with standard medical care vs. standard medical care plus a placebo in ambulatory patients with coronavirus disease 2019 (COVID‑19; nasal/oropharyngeal swabs reverse transcription‑PCR test results positive for severe acute respiratory syndrome coronavirus 2). The present study is a phase II prospective, two‑arm, parallel‑group, randomized, double‑blind placebo‑controlled clinical trial which analyzed 36 patients. Two aspects were evaluated during the 14‑day follow‑up period: i) The time for reaching a patient acceptable symptom state (PASS), and ii) the last day of each COVID‑19 symptom presentation. Adverse effects were evaluated. The clinical severity for all the patients in the study was mild (88.9%) and moderate (11.1%). The control (placebo) group achieved PASS on day 8.0±1.3, compared with day 4.4±0.8 in the mefenamic acid group (P=0.020, Kaplan‑Meier analyses using log‑rank tests). Patients that received mefenamic acid plus standard medical care had a ~16‑fold higher probability of achieving PASS on day 8 (adjusted RR, 15.57; 95% CI, 1.22‑198.71; P=0.035), compared with the placebo plus standard medical care group. All symptoms lasted for fewer days in the mefenamic acid group, compared with the placebo group; however, only the symptoms of headache (P=0.008), retro‑orbital eye pain (P=0.049), and sore throat (P=0.029) exhibited statistically significant differences. The experimental treatment produced no severe adverse effects. On the whole, the present study demonstrates that the administration of mefenamic acid markedly reduced the symptomatology and time to reach PASS in ambulatory patients with COVID‑19. Due to its probable antiviral effects and potent anti‑inflammatory mechanisms, mefenamic acid may prove to be useful in the treatment of COVID‑19, in combination with other drugs, including the new antivirals (remdesivir, molnupiravir, or favipiravir). However, future studies are also required to confirm these findings.

COVID-19 Vaccine Hesitancy among Patients with Inflammatory Bowel Disease Receiving Biologic Therapies in Kuwait: A Cross-Sectional Study

BACKGROUND

COVID-19 vaccinations have been shown to be effective in reducing risk of severe infection, hospitalization, and death. They have also been shown to be safe and effective in patients with inflammatory bowel disease (IBD) who are receiving biologic therapies. In this study, we aimed to evaluate the prevalence of vaccination among patients receiving biologic therapies for IBD.

METHODS

A single-center prospective cross-sectional study conducted at a tertiary care inflammatory bowel disease center in Kuwait. Data from patients with inflammatory bowel disease (IBD) who attended the gastroenterology infusion clinic from 1 June 2021 until 31 October 2021 were retrieved. Patients who received infliximab or vedolizumab at least six weeks before recruitment were included. The primary outcome was prevalence of COVID-19 vaccination. The secondary outcome was to assess whether prevalence of COVID-19 vaccination differed based on sex, age, type of biologic therapy and nationality.

RESULTS

The total number of inflammatory bowel disease (IBD) patients enrolled in the study was 280 (56.0% male and 44.0% female). Of the total, 112 (40.0%) patients were diagnosed with ulcerative colitis and 168 (60.0%) with Crohn's disease. The number of ulcerative colitis patients who were vaccinated was 49 (43.8%) and the number of Crohn's disease patients who were vaccinated was 68 (40.5%). The median age was 33.2 years and BMI was 24.8 kg/m2. With respect to the total number of patients, 117 (41.8%) were vaccinated with either BNT162b2 or ChAdOx1 nCoV-19 and 163 (58.2%) were not vaccinated. Female patients were more likely to receive the vaccine compared to male patients (83.0% vs. 63.8%, p < 0.001). In addition, patients above the age 50 were more likely to receive the vaccine than patients below the age of 50 (95.6% vs. 31.2% p < 0.001). Expatriates were more likely to receive the vaccine than citizens (84.8% vs. 25.0%, p < 0.001). There was no statistical difference between patients on infliximab and vedolizumab with regard to prevalence of vaccination (40.0% vs 48.0%, p = 0.34).

CONCLUSION

The overall prevalence of COVID-19 vaccination among patients with inflammatory bowel disease (IBD) on biologic therapies was lower than that of the general population and world health organization (WHO) recom-mendation. Female patients, patients above the age of 50, and expatriates were more likely to receive the vaccine. Physicians should reinforce the safety and efficacy of COVID-19 vaccines among patients, especially IBD patients on biologic therapies, who express hesitancy towards them.

COVID-19 immunopathology with emphasis on Th17 response and cell-based immunomodulation therapy: Potential targets and challenges

The role of the immune system against coronavirus disease 2019 (COVID-19) is unknown in many aspects, and the protective or pathologic mechanisms of the immune response are poorly understood. Pro-inflammatory cytokine release and a consequent cytokine storm can lead to acute respiratory distress syndrome (ARDS) and result in multi-organ failure. There are many T cell subsets during anti-viral immunity. The Th17-associated response, as a pro-inflammatory pathway, and its consequent outcomes in many autoimmune disorders play a fundamental role in progression of systemic hyper-inflammation during COVID-19. Therapeutic strategies based on immunomodulation therapy could be helpful for targeting hyper-inflammatory immune responses in COVID-19, especially Th17-related inflammation and hyper-cytokinemia. Cell-based immunotherapeutic approaches including mesenchymal stem cells (MSCs), tolerogenic dendritic cells (tolDCs) and regulatory T cells (Tregs) seem to be promising strategies as orchestrators of the immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this review, we highlight Th17-related immunopathology of SARS-CoV-2 infection and discuss cell-based immunomodulatory strategies and their mechanisms for regulation of the hyper-inflammation during COVID-19.

Inhibitory immune checkpoint molecules and exhaustion of T cells in COVID-19

COVID-19 (Coronavirus Disease) is an infectious disease caused by the coronavirus SARS-CoV-2 (Severe acute respiratory syndrome Coronavirus 2), which belongs to the genus Betacoronavirus. It was first identified in patients with severe respiratory disease in December 2019 in Wuhan, China. It mainly affects the respiratory system, and in severe cases causes serious lung infection or pneumonia, which can lead to the death of the patient. Clinical studies show that SARS-CoV-2 infection in critical cases causes acute tissue damage due to a pathological immune response. The immune response to a new coronavirus is complex and involves many processes of specific and non-specific immunity. Analysis of available studies has shown various changes, especially in the area of specific cellular immunity, including lymphopenia, decreased T cells (CD3+, CD4+ and CD8+), changes in the T cell compartment associated with symptom progression, deterioration of the condition and development of lung damage. We provide a detailed review of the analyses of immune checkpoint molecules PD-1, TIM-3, LAG-3 CTLA-4, TIGIT, BTLA, CD223, IDO-1 and VISTA on exhausted T cells in patients with asymptomatic to symptomatic stages of COVID-19 infection. Furthermore, this review may help to better understand the pathological T cell immune response and improve the design of therapeutic strategies for patients with SARS-CoV-2 infection.

Outcome of Critically Ill COVID-19 Patients According to the Setting of Corticosteroid Initiation-A Retrospective Observational Cohort Study

(1) Background: Corticosteroids lower 28-day all-cause mortality in critically ill COVID-19 patients. However, the outcome of COVID-19 patients referred to the intensive care unit (ICU) for respiratory deterioration despite corticosteroids initiated during hospitalization before ICU admission has been poorly investigated. Our objective was to determine survival according to corticosteroid initiation setting. (2) Methods: We conducted a cohort study including all successive critically ill COVID-19 patients treated with corticosteroids and managed in our ICU. We compared survival, whether corticosteroids were initiated before (Cb-group) or after ICU admission (Ca-group), using a propensity score matching. (3) Results: Overall, 228 patients (67 years (56–74); 168M/60F; invasive mechanical ventilation on admission, 17%) were included with 63 patients in the Cb-group and 165 patients in the Ca-group. Survival to hospital discharge was 43% versus 69%, respectively (p = 0.001). In a multivariable analysis, factors associated with death were age (odds ratio, 1.07; 95%-confidence interval, (1.04–1.11); p < 0.0001), the sequential organ failure assessment (SOFA) score on ICU admission (1.30 (1.14–1.50); p = 0.0001) and corticosteroid initiation before ICU admission (2.64 (1.30–5.43); p = 0.007). No significant differences in outcome related to corticosteroid regimen were found. (4) Conclusions: Critically ill COVID-19 patients transferred to the ICU with deterioration despite corticosteroids initiated before admission have a less favorable outcome than patients receiving corticosteroids initiated after ICU admission.

Immunomonitoring of Monocyte and Neutrophil Function in Critically Ill Patients: From Sepsis and/or Trauma to COVID-19

Immune cells and mediators play a crucial role in the critical care setting but are understudied. This review explores the concept of sepsis and/or injury-induced immunosuppression and immuno-inflammatory response in COVID-19 and reiterates the need for more accurate functional immunomonitoring of monocyte and neutrophil function in these critically ill patients. in addition, the feasibility of circulating and cell-surface immune biomarkers as predictors of infection and/or outcome in critically ill patients is explored. It is clear that, for critically ill, one size does not fit all and that immune phenotyping of critically ill patients may allow the development of a more personalized approach with tailored immunotherapy for the specific patient. In addition, at this point in time, caution is advised regarding the quality of evidence of some COVID-19 studies in the literature.

Systemic Anti-Cancer Therapy and Metastatic Cancer Are Independent Mortality Risk Factors during Two UK Waves of the COVID-19 Pandemic at University College London Hospital

An increased mortality risk was observed in patients with cancer during the first wave of COVID-19. Here, we describe determinants of mortality in patients with solid cancer comparing the first and second waves of COVID-19. A retrospective analysis encompassing two waves of COVID-19 (March-May 2020; December 2020-February 2021) was performed. 207 patients with cancer were matched to 452 patients without cancer. Patient demographics and oncological variables such as cancer subtype, staging and anti-cancer treatment were evaluated for association with COVID-19 mortality. Overall mortality was lower in wave two compared to wave one, HR 0.41 (95% CI: 0.30-0.56). In patients with cancer, mortality was 43.6% in wave one and 15.9% in wave two. In hospitalized patients, after adjusting for age, ethnicity and co-morbidities, a history of cancer was associated with increased mortality in wave one but not wave two. In summary, the second UK wave of COVID-19 is associated with lower mortality in hospitalized patients. A history of solid cancer was not associated with increased mortality despite the dominance of the more transmissible B.1.1.7 SARS-CoV-2 variant. In both waves, metastatic disease and systemic anti-cancer treatment appeared to be independent risk factors for death within the combined cancer cohort.

Comorbidity-associated glutamine deficiency is a predisposition to severe COVID-19

SARS-CoV-2 vaccinations have greatly reduced COVID-19 cases, but we must continue to develop our understanding of the nature of the disease and its effects on human immunity. Previously, we suggested that a dysregulated STAT3 pathway following SARS-Co-2 infection ultimately leads to PAI-1 activation and cascades of pathologies. The major COVID-19-associated metabolic risks (old age, hypertension, cardiovascular diseases, diabetes, and obesity) share high PAI-1 levels and could predispose certain groups to severe COVID-19 complications. In this review article, we describe the common metabolic profile that is shared between all of these high-risk groups and COVID-19. This profile not only involves high levels of PAI-1 and STAT3 as previously described, but also includes low levels of glutamine and NAD+, coupled with overproduction of hyaluronan (HA). SARS-CoV-2 infection exacerbates this metabolic imbalance and predisposes these patients to the severe pathophysiologies of COVID-19, including the involvement of NETs (neutrophil extracellular traps) and HA overproduction in the lung. While hyperinflammation due to proinflammatory cytokine overproduction has been frequently documented, it is recently recognized that the immune response is markedly suppressed in some cases by the expansion and activity of MDSCs (myeloid-derived suppressor cells) and FoxP3+ Tregs (regulatory T cells). The metabolomics profiles of severe COVID-19 patients and patients with advanced cancer are similar, and in high-risk patients, SARS-CoV-2 infection leads to aberrant STAT3 activation, which promotes a cancer-like metabolism. We propose that glutamine deficiency and overproduced HA is the central metabolic characteristic of COVID-19 and its high-risk groups. We suggest the usage of glutamine supplementation and the repurposing of cancer drugs to prevent the development of severe COVID-19 pneumonia.

COVID-19, what could sepsis, severe acute pancreatitis, gender differences, and aging teach us?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a potentially life-threatening disease, defined as Coronavirus Disease 19 (COVID-19). The most common signs and symptoms of this pathological condition include cough, fever, shortness of breath, and sudden onset of anosmia, ageusia, or dysgeusia. The course of COVID-19 is mild or moderate in more than 80% of cases, but it is severe or critical in about 14% and 5% of infected subjects respectively, with a significant risk of mortality. SARS-CoV-2 related infection is characterized by some pathogenetic events, resembling those detectable in other pathological conditions, such as sepsis and severe acute pancreatitis. All these syndromes are characterized by some similar features, including the coexistence of an exuberant inflammatory- as well as an anti-inflammatory-response with immune depression. Based on current knowledge concerning the onset and the development of acute pancreatitis and sepsis, we have considered these syndromes as a very interesting paradigm for improving our understanding of pathogenetic events detectable in patients with COVID-19. The aim of our review is: 1)to examine the pathogenetic mechanisms acting during the emergence of inflammatory and anti-inflammatory processes in human pathology; 2)to examine inflammatory and anti-inflammatory events in sepsis, acute pancreatitis, and SARS-CoV-2 infection and clinical manifestations detectable in patients suffering from these syndromes also according to the age and gender of these individuals; as well as to analyze the possible common and different features among these pathological conditions; 3)to obtain insights into our knowledge concerning COVID-19 pathogenesis. This approach may improve the management of patients suffering from this disease and it may suggest more effective diagnostic approaches and schedules of therapy, depending on the different phases and/or on the severity of SARS-CoV-2 infection.

Data-driven multi-scale mathematical modeling of SARS-CoV-2 infection reveals heterogeneity among COVID-19 patients

Patients with coronavirus disease 2019 (COVID-19) often exhibit diverse disease progressions associated with various infectious ability, symptoms, and clinical treatments. To systematically and thoroughly understand the heterogeneous progression of COVID-19, we developed a multi-scale computational model to quantitatively understand the heterogeneous progression of COVID-19 patients infected with severe acute respiratory syndrome (SARS)-like coronavirus (SARS-CoV-2). The model consists of intracellular viral dynamics, multicellular infection process, and immune responses, and was formulated using a combination of differential equations and stochastic modeling. By integrating multi-source clinical data with model analysis, we quantified individual heterogeneity using two indexes, i.e., the ratio of infected cells and incubation period. Specifically, our simulations revealed that increasing the host antiviral state or virus induced type I interferon (IFN) production rate can prolong the incubation period and postpone the transition from asymptomatic to symptomatic outcomes. We further identified the threshold dynamics of T cell exhaustion in the transition between mild-moderate and severe symptoms, and that patients with severe symptoms exhibited a lack of naïve T cells at a late stage. In addition, we quantified the efficacy of treating COVID-19 patients and investigated the effects of various therapeutic strategies. Simulations results suggested that single antiviral therapy is sufficient for moderate patients, while combination therapies and prevention of T cell exhaustion are needed for severe patients. These results highlight the critical roles of IFN and T cell responses in regulating the stage transition during COVID-19 progression. Our study reveals a quantitative relationship underpinning the heterogeneity of transition stage during COVID-19 progression and can provide a potential guidance for personalized therapy in COVID-19 patients.

Coronavirus disease 2019 (COVID-19) is currently destroying both lives and economies. However, patients infected with severe acute respiratory syndrome (SARS)-like coronavirus (SARS-CoV-2) usually present heterogeneous and complicated progressions, such as different incubation periods (short and long), symptoms (asymptomatic and symptomatic) and severity (mild-moderate and severe). Currently, various clinical data and experimental data are available from different countries, which has great significance for integrating different types of data to comprehensively understand the diverse disease progression in COVID-19 patients and guide individual treatment strategies. Here, we developed a multi-scale computational model to describe the dynamical process of patients infected with SARS-CoV-2, including intracellular viral dynamics, multicellular infection process, and immune responses. By combining data integration, stochastic simulation and quantitative analysis based on the multi-scale mathematical model, we addressed an important question regarding how IFN response and T cell exhaustion quantitatively affect heterogeneous progression in patients with respect to incubation periods, symptoms and severity. Furthermore, the efficacy of various therapeutic strategies for treating COVID-19 patients with different severity degrees was evaluated and validated. The computational framework in this study can also be extended to explore the dynamical process of other coronavirus infections.

Antibody Responses to COVID-19 Vaccination in Cancer: A Systematic Review

INTRODUCTION

After the results of phase III vaccine studies became available, the leading oncology societies recommended two doses of COVID-19 vaccination to all patients with cancer with no specific recommendation for tumor type and active treatments. However, the data on the COVID-19 vaccine efficacy in cancer patients is limited due to exclusion of cancer patients from most vaccine clinical trials. Therefore, we systemically reviewed the available evidence evaluating the antibody responses in cancer patients.

METHODS

We conducted a systematic search from the Pubmed database and calculated risk differences (RD) and 95% confidence intervals (CI) to compare seroconversion rates between cancer patients and controls using the Review Manager software, version 5.3.

RESULTS

Our systematic search retrieved a total 27 studies and we included 17 studies with control arms in the analyses. Cancer patients had significantly lower seroconversion rates (37.3%) than controls (74.1%) (RD: -0.44, 95% CI: -0.52, -0.35, p<0.001) with first vaccine dose. After two doses, the seroconversion rates were 99.6% in control arm and 78.3% in cancer patients (RD: -0.19, 95% CI: -0.28, -0.10, p<0.001). The difference in seroconversion rates was more pronounced patients with hematologic malignancies (72.6%) (RD: -0.25, 95% CI: -0.27, -0.22, p<0.001) than patients with solid tumors (91.6%) (RD: -0.09, 95% CI: -0.13, -0.04, p<0.003) and patients in remission (RD: -0.10, 95% CI: -0.14, -0.06, p<0.001).

CONCLUSION

In conclusion, COVID-19 vaccine seroconversion rates were significantly lower in patients with hematological malignancies and patients under active treatment. Further research focusing on the approaches to improve vaccine efficacy and exploration of novel treatment options is urgently needed for these patients.

Novel therapeutic drug strategies to tackle immune-oncological challenges faced by cancer patients during COVID-19

INTRODUCTION

For the clinical treatment of cancer patients, coronavirus (SARS-CoV-2) can cause serious immune-related problems. Cancer patients, who experience immunosuppression due to the pathogenesis and severity of disease, may become more aggressive due to multiple factors such as age, comorbidities, and immunosuppression. In this pandemic era, COVID-19 causes lymphopenia, cancer cell awakening, inflammatory diseases, and a cytokine storm that worsens disease-related morbidity and prognosis.

AREAS COVERED

We discuss all the risk factors of COVID-19 associated with cancer patients and propose new strategies to use antiviral and anticancer drugs for therapeutic purposes. We bring new drugs, cancers and COVID-19 treatment strategies together to address the immune system challenges faced by oncologists.

EXPERT OPINION

The chronic inflammatory microenvironment caused by COVID-19 awakens dormant cancer cells through inflammation and autoimmune activation. Drug-related strategies to ensure that clinical treatment can reduce the susceptibility of cancer patients to COVID-19, and possible counter-measures to minimize the harm caused by the COVID-19 have been outlined. The response to the pandemic and recovery has been elaborated, which can provide information for long-term cancer treatment and speed up the optimization process.

Does prior exposure to immune checkpoint inhibitors treatment affect incidence and mortality of COVID-19 among the cancer patients: The systematic review and meta-analysis

BACKGROUND

Immune checkpoint inhibitors (ICIs) treatment among cancer patients has been shown to have antiviral effects by reactivating exhausted T cells. However, they could also trigger inflammatory storm. Therefore, prior exposure to ICIs may influence the risk of SARS-CoV2 infection and subsequent mortality. Recent results from studies of ICIs treatment on incidence and mortality of COVID-19 are controversial.

MATERIALS AND METHODS

We searched databases PubMed, Embase, ISI of Knowledge, Cochrane Central Register of Controlled Trials (CENTRAL), as well as pre-print databases (MedRxiv and BioRxiv) for retrospective and prospective studies comparing ICIs versus other antitumor treatments in cancer patients in the area of COVID-19 pandemic. The primary outcome was the incidence of COVID-19. The secondary outcomes were mortality of COVID-19.

RESULTS

Twenty-three studies with a total of 117,735 patients were selected. Compared with other antitumor treatments, prior exposure to ICIs had not an increased risk of incidence [Odds ratio (OR), 0.84; 95% confidence interval (CI), 0.60-1.18; P = 0.32] and mortality (OR, 1.22; 95% CI, 0.91-1.62; P = 0.18) of COVID-19 infectioin. Our subgroup and meta-regression analyses indicated that prior exposure to ICIs may reduce the incidence of COVID-19 in metastatic cancer patients.

CONCLUSIONS

There was no significant difference on incidence and mortality of COVID-19 between prior exposure to ICIs with other anti-tumor treatments. ICIs may reduce infection susceptibility of COVID-19 in metastatic cancer patients.

Immune response (IgG) following full inoculation with BNT162b2 COVID‑19 mRNA among healthcare professionals

Soon after the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in December, 2019, numerous research teams, assisted by vast capital investments, achieved vaccine development in a fraction of time. However, almost 8 months following the initiation of the European vaccination programme, the need for prospective monitoring of the vaccine-induced immune response, its determinants and related side-effects remains a priority. The present study aimed to quantify the immune response following full vaccination with the BNT162b2 coronavirus disease 2019 (COVID-19) mRNA vaccine by measuring the levels of immunoglobulin G (IgG) titers in healthcare professionals. Moreover, common side-effects and factors associated with IgG titers were identified. For this purpose, blood samples from 517 individuals were obtained and analysed. Blood sampling was performed at a mean period of 69.0±23.5 days following the second dose of the vaccine. SARS-CoV-2 IgG titers had an overall mean value of 4.23±2.76. Females had higher titers than males (4.44±2.70 and 3.89 ±2.84, respectively; P=0.007), while non-smokers had higher titers than smokers (4.48±2.79 and 3.80±2.64, respectively; P=0.003). An older age was also associated with lower antibody titers (P<0.001). Moreover, the six most prevalent adverse effects were pain at the injection site (72.1%), generalized fatigue (40.5%), malaise (36.3%), myalgia (31,0%), headache (25.8%) and dizziness/weakness (21.6%). The present study demonstrated that the immune response after receiving the BNT162b2 COVID-19 mRNA vaccine is dependent on various modifiable and non-modifiable factors. Overall, the findings of the present study highlight two key aspects of the vaccination programs: First, the need for prospective immunosurveillance studies in order to estimate the duration of immunity, and second, the need to identify those individuals who are at a greater risk of developing low IgG titers in order to evaluate the need for a third dose of the vaccine.

Potential protective role of the anti-PD-1 blockade against SARS-CoV-2 infection

The outbreak of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Wuhan, China, in December 2019, and its global dissemination became the coronavirus disease 2019 (COVID-19) pandemic declared by the World Health Organization (WHO) on 11 March 2020. In patients undergoing immunotherapy, the effect and path of viral infection remain uncertain. In addition, viral-infected mice and humans show T-cell exhaustion, which is identified after infection with SARS-CoV-2. Notably, they regain their T-cell competence and effectively prevent viral infection when treated with anti-PD-1 antibodies. Four clinical trials are officially open to evaluate anti-PD-1 antibody administration's effectiveness for cancer and non-cancer individuals influenced by COVID-19 based on these findings. The findings may demonstrate the hypothesis that a winning strategy to combat SARS-CoV-2 infection could be the restoration of exhausted T-cells. In this review, we outline the potential protective function of the anti-PD-1 blockade against SARS-CoV-2 infection with the aim to develop SARS-CoV-2 therapy.

Interplay between Neutrophils, NETs and T-Cells in SARS-CoV-2 Infection-A Missing Piece of the Puzzle in the COVID-19 Pathogenesis?

Since the end of 2019, a new, dangerous virus has caused the deaths of more than 3 million people. Efforts to fight the disease remain multifaceted and include prophylactic strategies (vaccines), the development of antiviral drugs targeting replication, and the mitigation of the damage associated with exacerbated immune responses (e.g., interleukin-6-receptor inhibitors). However, numerous uncertainties remain, making it difficult to lower the mortality rate, especially among critically ill patients. While looking for a new means of understanding the pathomechanisms of the disease, we asked a question-is our immunity key to resolving these uncertainties? In this review, we attempt to answer this question, and summarize, interpret, and discuss the available knowledge concerning the interplay between neutrophils, neutrophil extracellular traps (NETs), and T-cells in COVID-19. These are considered to be the first line of defense against pathogens and, thus, we chose to emphasize their role in SARS-CoV-2 infection. Although immunologic alterations are the subject of constant research, they are poorly understood and often underestimated. This review provides background information for the expansion of research on the novel, immunity-oriented approach to diagnostic and treatment possibilities.

Safeguarding COVID-19 and cancer management: drug design and therapeutic approach

Recent clinical cohort studies have highlighted that there is a three-fold greater SARS-Cov-2 infection risk in cancer patients, and overall mortality in individuals with tumours is increased by 41% with respect to general COVID-19 patients. Thus, access to therapeutics and intensive care is compromised for people with both diseases (comorbidity) and there is risk of delayed access to diagnosis. This comorbidity has resulted in extensive burden on the treatment of patients and health care system across the globe; moreover, mortality of hospitalized patients with comorbidity is reported to be 30% higher than for individuals affected by either disease. In this data-driven review, we aim specifically to address drug discoveries and clinical data of cancer management during the COVID-19 pandemic. The review will extensively address the treatment of COVID-19/cancer comorbidity; treatment protocols and new drug discoveries, including the description of drugs currently available in clinical settings; demographic features; and COVID-19 outcomes in cancer patients worldwide.

Clinical and immunologic implications of COVID-19 in patients with melanoma and renal cell carcinoma receiving immune checkpoint inhibitors

The clinical and immunologic implications of the SARS-CoV-2 pandemic for patients with cancer receiving systemic anticancer therapy have introduced a multitude of clinical challenges and academic controversies. This review summarizes the current evidence, discussion points, and recommendations regarding the use of immune checkpoint inhibitors (ICIs) in patients with cancer during the SARS-CoV-2 pandemic, with a focus on patients with melanoma and renal cell carcinoma (RCC). More specifically, we summarize the theoretical concepts and available objective data regarding the relationships between ICIs and the antiviral immune response, along with recommended clinical approaches to the management of melanoma and RCC patient cohorts receiving ICIs throughout the course of the COVID-19 pandemic. Additional insights regarding the use of ICIs in the setting of current and upcoming COVID-19 vaccines and broader implications toward future pandemics are also discussed.

A multidisciplinary approach remains the best strategy to improve and strengthen the management of ovarian cancer (Review)

Ovarian cancer represents one of the most aggressive female tumors worldwide. Over the decades, the therapeutic options for the treatment of ovarian cancer have been improved significantly through the advancement of surgical techniques as well as the availability of novel effective drugs able to extend the life expectancy of patients. However, due to its clinical, biological and molecular complexity, ovarian cancer is still considered one of the most difficult tumors to manage. In this context, several studies have highlighted how a multidisciplinary approach to this pathology improves the prognosis and survival of patients with ovarian cancer. On these bases, the aim of the present review is to present recent advantages in the diagnosis, staging and treatment of ovarian cancer highlighting the benefits of a patient‑centered care approach and on the importance of a multidisciplinary team for the management of ovarian cancer.

Current and innovative methods for the diagnosis of COVID‑19 infection (Review)

The Coronavirus Disease 2019 (COVID‑19) pandemic has forced the scientific community to rapidly develop highly reliable diagnostic methods in order to effectively and accurately diagnose this pathology, thus limiting the spread of infection. Although the structural and molecular characteristics of the severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) were initially unknown, various diagnostic strategies useful for making a correct diagnosis of COVID‑19 have been rapidly developed by private research laboratories and biomedical companies. At present, rapid antigen or antibody tests, immunoenzymatic serological tests and molecular tests based on RT‑PCR are the most widely used and validated techniques worldwide. Apart from these conventional methods, other techniques, including isothermal nucleic acid amplification techniques, clusters of regularly interspaced short palindromic repeats/Cas (CRISPR/Cas)‑based approaches or digital PCR methods are currently used in research contexts or are awaiting approval for diagnostic use by competent authorities. In order to provide guidance for the correct use of COVID‑19 diagnostic tests, the present review describes the diagnostic strategies available which may be used for the diagnosis of COVID‑19 infection in both clinical and research settings. In particular, the technical and instrumental characteristics of the diagnostic methods used are described herein. In addition, updated and detailed information about the type of sample, the modality and the timing of use of specific tests are also discussed.

Current and innovative methods for the diagnosis of COVID‑19 infection (Review)

The Coronavirus Disease 2019 (COVID‑19) pandemic has forced the scientific community to rapidly develop highly reliable diagnostic methods in order to effectively and accurately diagnose this pathology, thus limiting the spread of infection. Although the structural and molecular characteristics of the severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) were initially unknown, various diagnostic strategies useful for making a correct diagnosis of COVID‑19 have been rapidly developed by private research laboratories and biomedical companies. At present, rapid antigen or antibody tests, immunoenzymatic serological tests and molecular tests based on RT‑PCR are the most widely used and validated techniques worldwide. Apart from these conventional methods, other techniques, including isothermal nucleic acid amplification techniques, clusters of regularly interspaced short palindromic repeats/Cas (CRISPR/Cas)‑based approaches or digital PCR methods are currently used in research contexts or are awaiting approval for diagnostic use by competent authorities. In order to provide guidance for the correct use of COVID‑19 diagnostic tests, the present review describes the diagnostic strategies available which may be used for the diagnosis of COVID‑19 infection in both clinical and research settings. In particular, the technical and instrumental characteristics of the diagnostic methods used are described herein. In addition, updated and detailed information about the type of sample, the modality and the timing of use of specific tests are also discussed.