The role of IL-6/lymphocyte ratio in the peripheral blood of severe patients with COVID-19

Interleukin-62/lymphocyte as a proposed predictive index for COVID-19 patients treated with monoclonal antibodies

In a convenience sample of 93 patients treated with monoclonal antibodies (moAbs) against SARS-CoV-2, the interleukin-62/lymphocyte count ratio (IL-62/LC) was able to predict clinical worsening both in early stages of COVID-19 and in oxygen-requiring patients. Moreover, we analysed 18 most at-risk patients with asymptomatic or mild disease treated with both moAbs and antiviral treatment and found that only 2 had clinical progression, while patients with a similar risk were reported to have an unfavourable outcome in most cases from recent data. In only one of our 18 patients, clinical progression was attributable to COVID-19, and in the other cases, clinical progression was observed despite IL-62/LC being above the risk cut-off. In conclusion, IL-62/LC may be a valuable method to identify patients requiring more aggressive treatments both in earlier and later stages of the disease; however, most at-risk patients can be protected from clinical worsening by combining moAbs and antivirals, even if levels of the IL-62/LC biomarker are lower than the risk cut-off.

Differentially Expressed Inflammatory Cell Death-Related Genes and the Serum Levels of IL-6 are Determinants for Severity of Coronaviruses Diseases-2019 (COVID-19)

Background

Inflammatory cell death, PANoptosis, has been suggested to orchestrate the lymphocyte decrement among coronavirus disease-2019 (COVID-19) patients. The main aim of this study was to examine the differences in the expression of key genes related to inflammatory cell death and their correlation with lymphopenia in the mild and severe types of COVID-19 patients.

Materials and Methods

Eighty-eight patients (36 to 60 years old) with mild (n = 44) and severe (n = 44) types of COVID-19 were enrolled. The expression of key genes related to apoptosis (FAS-associated death domain protein, FADD), pyroptosis (ASC (apoptosis-associated speck-like protein containing caspase activation and recruitment domains (CARD)), the adapter protein ASC binds directly to caspase-1 and is critical for caspase-1 activation in response to a broad range of stimuli), and necroptosis (mixed lineage kinase domain-like, MLKL) genes were examined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assay, and compared between the groups. The serum levels of interleukin (IL)-6 were measured by enzyme-linked immunosorbent assay (ELISA) assay.

Results

A major increase in the expression of FADD, ASC, and MLKL-related genes in the severe type of patients was compared to the mild type of patients. The serum levels of IL-6 similarly indicated a significant increase in the severe type of the patients. A significant negative correlation was detected between the three genes' expression and the levels of IL-6 with the lymphocyte counts in both types of COVID-19 patients.

Conclusion

Overall, the main regulated cell-death pathways are likely to be involved in lymphopenia in COVID-19 patients, and the expression levels of these genes could potentially predict the patients' outcome.

Reduced IFN-γ levels along with changes in hematologic and immunologic parameters are key to COVID-19 severity in Bangladeshi patients

The manifestation of coronavirus disease 2019 (COVID-19) severity and mortality has been associated with dysregulation of the immune response, often influenced by racial disparities and conferred by changes in hematologic and immunologic parameters. These biological and hematologic parameters as well as cytokine profiles were investigated in a cohort of 61 COVID-19-positive patients (categorized into mild, moderate, and severe groups) from Bangladesh using standard analytical methods. The data reported that the interleukin (IL)-4 and IL-6 levels were significantly increased, whereas the levels of interferon (IFN)-γ were significantly reduced in patients with severe COVID-19 (p < 0.05) compared with those in patients with mild and/or moderate COVID-19. The extent of erythrocyte sedimentation rate (ESR); neutrophil count; and levels of ferritin, C-reactive protein (CRP), and D-dimer (p < 0.05) were found to be significantly increased, whereas the white blood cell (WBC), lymphocyte, eosinophil, and platelet counts (p < 0.05) were observed to be significantly reduced in patients with severe COVID-19 compared with those in the patients in other 2 groups. Our study exhibited a significantly higher IL-6-to-lymphocyte ratio in patients with severe COVID-19 than in those with mild and moderate COVID-19. The calculated neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and ferritin-to-ESR ratio were significantly increased in patients with severe COVID-19. The increase in the IL-4 and IL-6 levels along with CRP and D-dimer levels may envisage a hyperinflammatory environment and immune dysregulation, which contribute to prolonged viral persistence, leading to severe disease. However, the reduced level of IFN-γ can be attributed to a less fatality toll in Bangladesh compared with that in the rest of the world.

SHORT-TERM INFLAMMATORY BIOMARKER PROFILES ARE ASSOCIATED WITH DEFICIENT MITOCHONDRIAL BIOENERGETICS IN LYMPHOCYTES OF SEPTIC SHOCK PATIENTS-A PROSPECTIVE COHORT STUDY

ABSTRACT

Introduction: A biomarker strategy based on the quantification of an immune profile could provide a clinical understanding of the inflammatory state in patients with sepsis and its potential implications for the bioenergetic state of lymphocytes, whose metabolism is associated with altered outcomes in sepsis. The objective of this study is to investigate the association between mitochondrial respiratory states and inflammatory biomarkers in patients with septic shock. Methods: This prospective cohort study included patients with septic shock. Routine, complex I, complex II respiration, and biochemical coupling efficiency were measured to evaluate mitochondrial activity. We measured IL-1ß, IL-6, IL-10, total lymphocyte count, and C-reactive protein levels on days 1 and 3 of septic shock management as well as mitochondrial variables. The variability of these measurements was evaluated using delta counts (days 3-1 counts). Results: Sixty-four patients were included in this analysis. There was a negative correlation between complex II respiration and IL-1ß (Spearman ρ, -0.275; P = 0.028). Biochemical coupling efficiency at day 1 was negative correlated with IL-6: Spearman ρ, -0.247; P = 0.05. Delta complex II respiration was negatively correlated with delta IL-6 (Spearman ρ, -0.261; P = 0.042). Delta complex I respiration was negatively correlated with delta IL-6 (Spearman ρ, -0.346; P = 0.006), and delta routine respiration was also negatively correlated with both delta IL-10 (Spearman ρ, -0.257; P = 0.046) and delta IL-6 (Spearman ρ, -0.32; P = 0.012). Conclusions: The metabolic change observed in mitochondrial complex I and complex II of lymphocytes is associated with a decrease in IL-6 levels, which can signal a decrease in global inflammatory activity.

Interleukin-6 and Outcome of Chronic Hemodialysis Patients with SARS-CoV-2 Pneumonia

Background and Objectives: Chronic hemodialysis (CHD) patients are at increased risk of SARS-CoV-2 infection and the related complications and mortality of COVID-19 due to the high rate of comorbidities combined with advanced age. This observational study investigated the clinical manifestations of SARS-CoV-2 infection in CHD and the risk factors for patients′ death. Materials and Methods: The study included 26 CHD patients with SARS-CoV-2 pneumonia detected by positive RT-PCR on nasopharyngeal swabs and high-resolution computed tomography at hospital admission, aged 71 + 5.9 years, 14 of which (53.8%) were male, 20 (77%) under hemodiafiltration, and 6 (23%) on standard hemodialysis, with a median follow-up of 30 days. Results: Simple logistic regression analysis revealed that the factors associated with a higher risk of death were older age (OR: 1.133; 95%CI: 1.028−1.326, p = 0.0057), IL-6 levels at admission (OR: 1.014; 95%CI: 1.004−1.028, p = 0.0053), and C-reactive protein (OR: 1.424; 95%CI: 1.158−2.044, p < 0.0001). In the multiple logistic regression model, circulating IL-6 values at admission remained the only significant prognosticator of death. The ROC curve indicated the discriminatory cut-off value of 38.20 pg/mL of blood IL-6 for predicting death in chronic hemodialysis patients with SARS-CoV-2 pneumonia (sensitivity: 100%; specificity: 78%; AUC: 0.8750; p = 0.0027). Conclusions: This study identified a threshold of IL-6 levels at hospital admission for death risk in CHD patients with SARS-CoV-2 pneumonia. This might represent a valuable outcome predictor, feasibly better than other clinical, radiological, or laboratory parameters and preceding the IL-6 peak, which is unpredictable.

Inflammatory Biomarkers Associated with In-Hospital Mortality in Critical COVID-19 Patients

The COVID-19 pandemic poses global healthcare challenges due to its unpredictable clinical course. The aim of this study is to identify inflammatory biomarkers and other routine laboratory parameters associated with in-hospital mortality in critical COVID-19 patients. We performed a retrospective observational study on 117 critical COVID-19 patients. Following descriptive statistical analysis of the survivor and non-survivor groups, optimal cut-off levels for the statistically significant parameters were determined using the ROC method, and the corresponding Kaplan-Meier survival curves were calculated. The inflammatory parameters that present statistically significant differences between survivors and non-survivors are IL-6 (p = 0.0004, cut-off = 27.68 pg/mL), CRP (p = 0.027, cut-off = 68.15 mg/L) and IL-6/Ly ratio (p = 0.0003, cut-off = 50.39). Additionally, other statistically significant markers are creatinine (p = 0.031, cut-off = 0.83 mg/dL), urea (p = 0.0002, cut-off = 55.85 mg/dL), AST (p = 0.0209, cut-off = 44.15 U/L), INR (p = 0.0055, cut-off = 1.075), WBC (p = 0.0223, cut-off = 11.68 × 10⁹/L) and pH (p = 0.0055, cut-off = 7.455). A survival analysis demonstrated significantly higher in-hospital mortality rates of patients with values of IL-6, IL-6/Ly, AST, INR, and pH exceeding previously mentioned thresholds. In our study, IL-6 and IL-6/Ly have a predictive value for the mortality of critically-ill patients diagnosed with COVID-19. The integration of these parameters with AST, INR and pH could contribute to a prognostic score for the risk stratification of critical patients, reducing healthcare costs and facilitating clinical decision-making.

A systematic review and meta-analysis of the association between the neutrophil, lymphocyte, and platelet count, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio and COVID-19 progression and mortality

BACKGROUND AND AIMS

Severe manifestations of coronavirus disease 2019 (COVID-19) are associated with alterations in blood cells that regulate immunity, inflammation, and hemostasis. We conducted an updated systematic review and meta-analysis of the association between the neutrophil, lymphocyte, and platelet count, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR), and COVID-19 progression and mortality.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Scopus for studies published between January 2020 and June 2022.

RESULTS

In 71 studies reporting the investigated parameters within 48 hours of admission, higher NLR (HR 1.21, 95% CI 1.16 to 1.27, p < 0.0001), relative neutrophilia (HR 1.62, 95% CI 1.46 to 1.80, p < 0.0001), relative lymphopenia (HR 1.62, 95% CI 1.27 to 2.08, p < 0.001), and relative thrombocytopenia (HR 1.74, 95% CI 1.36 to 2.22, p < 0.001), but not PLR (p = 0.11), were significantly associated with disease progression and mortality. Between-study heterogeneity was large-to-extreme. The magnitude and direction of the effect size were not modified in sensitivity analysis.

CONCLUSIONS

NLR and neutrophil, lymphocyte, and platelet count significantly discriminate COVID-19 patients with different progression and survival outcomes. (PROSPERO registration number: CRD42021267875).

Deciphering the balance of IL-6/IL-10 cytokines in severe to critical COVID-19 patients

The severity of COVID-19 is largely determined by the inflammatory response, a “Cytokine storm,” that involves both pro- and anti-inflammatory cytokines. In the current study we investigated the balance of pro- and anti-inflammatory status as represented by the levels of IL-6/IL-10 in severe to critical COVID-19 patients. 66 confirmed COVID-19 patients admitted to the ICU were categorized into groups according to the mortality and respiratory failure. Data were collected retrospectively in ICU, including a peripheral immune cells and infection-related biomarker CRP. The measurements of cytokine levels were performed by Immulite analyzer for IL-6 and ELISA sandwich for IL-10. In addition, longitudinal measurement of IL-6 was performed during 5 days post admission. Longitudinal assays showed that IL-6 was sustained at a medium level within 5 days post admission in severe cases who survived or not requiring mechanical ventilation, whereas it was sustained at high levels throughout the disease course in either deceased cases or who developed respiratory failure. The ratio of IL-6/lymphocytes was positively correlated with the risk of mortality, while IL-10/lymphocytes ratio could predict respiratory failure in ICU. IL-6/IL-10 profiling revealed that deceased patients have different magnitudes of both IL-6 and IL-10 cytokine release. Notably, excessive levels of IL-6 concomitant with high levels of IL-10 were more common in diseased COVID-19 patients. Taking into account the IL-6/IL-10 profiling may help clinicians to identify the right time of anti-inflammation treatment and select patients who will respond to anti-cytokine therapies and maintain an adequate inflammatory response for SARS-CoV-2 clearance.

Prognostic role of Interleukin-6/lymphocytes ratio in SARS-CoV2 related pneumonia

Introduction and aim

Materials and methods

Results

Conclusion

The Association between TNF-α, IL-6, and Vitamin D Levels and COVID-19 Severity and Mortality: A Systematic Review and Meta-Analysis

BACKGROUND

An increasing number of scientific journals have proposed a connection between tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) and the severity of COVID-19. Vitamin D has been discussed as a potential therapy for COVID-19 due to its immunomodulatory effects. This meta-analysis aims to determine the relationship, if any, between TNF-α, IL-6, vitamin D, and COVID-19 severity and mortality.

METHODS

The design of the study is a systematic review and meta-analysis. A literature search is performed using PubMed, Cochrane, ProQuest, and Google Scholar.

RESULTS

TNF-α insignificantly increases the risk of COVID-19 severity (adjusted odds ratio (aOR) = 1.0304; 95% CI 0.8178-1.2983; p = 0.80) but significantly increases the risk of COVID-19 mortality (crude hazard ratio (HR) = 1.0640; 95% CI 1.0259-1.1036; p = 0.0009). IL-6 significantly increases the risk of COVID-19 severity (aOR = 1.0284; 95% CI 1.0130-1.0441; p = 0.0003) and mortality (aOR = 1.0076; 95% CI 1.0004-1.0148; p = 0.04; adjusted hazard ratio (aHR) = 1.0036; 95% CI 1.0010-1.0061; p = 0.006). There is a statistically insignificant difference of the mean vitamin D levels between patients with severe COVID-19 and non-severe COVID-19 (mean difference (MD) = -5.0232; 95% CI 11.6832-1.6368; p = 0.14). A vitamin D deficiency insignificantly increases the risk of mortality of COVID-19 patients (aOR = 1.3827; 95% CI 0.7103-2.6916; p = 0.34).

CONCLUSION

IL-6 is an independent prognostic factor towards COVID-19 severity and mortality.

Interleukin-6 in SARS-CoV-2 induced disease: Interactions and therapeutic applications

Interleukin-6 (IL-6) is a multi-tasking cytokine that represents high activity in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and cancer. High concentration of this pleiotropic cytokine accounts for hyperinflammation and cytokine storm, and is related to multi-organ failure in patients with SARS-CoV-2 induced disease. IL-6 promotes lymphopenia and increases C-reactive protein (CRP) in such cases. However, blockade of IL-6 is not a full-proof of complete response. Hypoxia, hypoxemia, aberrant angiogenesis and chronic inflammation are inter-related events occurring as a response to the SARS-CoV-2 stimulatory effect on high IL-6 activity. Taking both pro- and anti-inflammatory activities will make complex targeting IL-6 in patient with SARS-CoV-2 induced disease. The aim of this review was to discuss about interactions occurring within the body of patients with SARS-CoV-2 induced disease who are representing high IL-6 levels, and to determine whether IL-6 inhibition therapy is effective for such patients or not. We also address the interactions and targeted therapies in cancer patients who also have SARS-CoV-2 induced disease.