Immune Disorder in Atherosclerotic Cardiovascular Disease - Clinical Implications of Using Circulating T-Cell Subsets as Biomarkers

Prognostic Value of Neutrophil/Lymphocyte Ratio for Pulmonary Embolism: A Meta-Analysis and External Validation

BACKGROUND

Prognostic value of neutrophil/lymphocyte ratio (NLR) for pulmonary embolism (PE) has been reported in several retrospective studies. The purpose of this investigation was to perform a pooled analysis and external validation of predictive value of NLR.

METHODS

PubMed, Embase, and Cochrane databases were searched from inception to November 5, 2022. A random effects model was used. Grade was used to evaluate the certainty of evidence. External validation was conducted in clinical cohorts before and after a propensity scoring matching (PSM). Covariates include basic clinical characteristics, such as age, gender, etc. The value of NLR in prediction model was also evaluated.

RESULTS

A total of 15 studies comprising 5,874 patients were included. Pooled risk ratio of NLR was 2.33 (95% confidence interval [CI]: 1.97-2.75), with an area under the curve of 0.78 (95% CI: 0.74-0.81), a sensitivity of 0.75 (95% CI: 0.71-0.79), a specificity of 0.67 (95% CI: 0.61-0.73), and a median cut-off value of 5.7. Grade of Recommendations Assessment Development and Evaluation (GRADE) certainty analysis showed the quality of the evidence was moderate. Before (n = 336) and after (n = 152) propensity scoring matching, risk ratio of NLR was 2.69 (95% CI: 1.04-6.97) and 6.58 (95% CI: 1.99-17.75). A prediction model consisting of NLR, age, D-dimer, and simplified PE severity index had an area under the curve of 0.809 (95% CI: 0.738-0.88), a sensitivity of 0.638 (95% CI: 0.511-0.745), and a specificity of 0.851 (95% CI: 0.709-0.917). Net reclassification index (12%, P = 0.035) and integrated discrimination improvement (17%, P = 0.022) indicated an improvement caused by NLR.

CONCLUSIONS

Prognostic value of NLR for PE was confirmed by meta-analysis and validated in an independent cohort, deserving further clinical application.

Correlation of apolipoprotein A‐I with T cell subsets and interferon‐ү in coronary artery disease

Background

The association of Apolipoprotein A‐I (APOAI) with T cell subsets and interferon‐ү (IFN‐γ) in patients with coronary artery disease (CAD) has been not reported. Thus, this study aimed to investigate the association of APOAI with T cell subsets and IFN‐γ in CAD.

Methods

This study included a total of 107 patients with CAD including acute coronary syndrome and chronic coronary syndrome. T cell subsets, and CD3‐CD56+ natural killer cells were quantified by flow cytometric analysis. The serum concentrations of IFN‐ү were measured by enzyme‐linked immunosorbent assay. Lipid profiles, C‐reactive protein (CRP), and fibrinogen were measured in the clinical laboratory. Clinical data was obtained duration hospitalization.

Results

The CD4+ T cells were higher in patients of the low‐APOAI group (<median: 1.2 mmol/L) than in patients of the high‐APOAI group(≥median: 1.2 mmol/L) (p < .05). The CD8+ T cells were lower in patients of the low APOAI group than in patients of the high‐APOAI group (p < .05). APOAI was inversely associated with CD4+ T cells, IFN‐γ, and was positively associated with CD8+ T cells (p < .05). No correlation was observed between CD3 + CD56+ cells, regulatory T cells (Tregs), and CD3‐CD56+ natural killer cells and APOAI (p > .05). The high‐density lipoprotein cholesterol (HDL‐C) was also inversely associated with CD4+ T cells (p < .05), and positively associated with CD8+ T cells (p < .05). Lastly, APOA1 and HDL‐C did not correlated with fibrinogen and CRP (p > .05).

Conclusion

The present study demonstrated the correlation of APOAI with T cell subsets and IFN‐γ in CAD. These results provided novel information for the regulatory action between APOAI and T cell subsets and inflammatory immunity in CAD.

Platelet/Lymphocyte Ratio Predicted Long-Term Prognosis for Acute Upper Extremity Deep Vein Thrombosis from a Retrospective Study

Background

In this study, we aimed to determine the mortality risk factors and whether placement of a vena cava filter improves the prognosis of acute upper extremity deep vein thrombosis (UEDVT).

Methods

Clinical data and follow-up results were retrospectively analyzed. Cox regression analysis was conducted to identify the risk factors associated with all-cause mortality in all patients and subgroups of patients. Results are expressed as hazard ratio (HR) with 95% confidence intervals (95% CI). Receiver operating characteristic curves (ROC) were used to determine the optimal cut-off value. Kaplan-Meier survival curves were constructed and compared by the Log rank test.

Results

The study cohort comprised 109 patients of median age 56 years (47.5, 64.5). The median follow-up time was 25 months (8, 47): 39 patients (35.8%) had died by 12 months, 55 (50.5%) by 36 months, and 60 (55%) by the end of follow-up. Presence of malignancy (HR: 5.882, 95% CI: 2.128-16.667), D-dimer (HR: 1.56, 95% CI: 1.09-1.94), platelet/lymphocyte ratio (PLR; HR: 2.02, 95% CI: 1.15-3.54), and the systemic immune/inflammatory index (SII; HR: 1.471, 95% CI: 1.062-1.991) were identified as independent risk factors for mortality. Subgroup analysis of patients with malignancy determined gender (HR: 2.936, 95% CI: 1.599-5.393) and PLR (HR: 1.427,95% CI: 1.023-1.989) as independent risk factors. Kaplan-Meier analysis showed that the mortality rate was much higher in patients with malignancy, high D-dimer (≥ 0.92ug/mL), high PLR (≥ 291) and high SII (≥ 1487). However, there was no significant difference between patients with and without vena cava filters.

Conclusion

In this study, we identified PLR as an new independent predictor of mortality in patients with acute UEDVT. Emergency placement of a vena cava filter did not improve long-term prognosis.

The Association of Neutrophil-Lymphocyte Ratio with Venous Thromboembolism: A Systematic Review and Meta-Analysis

The neutrophil–lymphocyte ratio(NLR) has been used for diagnosing venous thromboembolism (VTE). We aimed to assess the accuracy of NLR to diagnose VTE by meta-analysis. Systematic electronic searches were conducted June 2, 2021 in PubMed, Embase(Ovid), and Cochrane Library. The search did not have any language or time restriction applied. Our search strategy was based on keywords in combination with both medical subject headings (MeSH) terms and text words. The diagnostic odds ratio, summary receiver operating characteristics, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were estimated. 10 articles with 1513 VTE participants and 2593 control participants were included for quantitative synthesis. The pooled values were as follows: sensitivity = 0.68(95% CI 0.45-0.84), specificity = 0.73(95% CI 0.6-0.83), positive likelihood ratio = 2.5(95% CI 1.8-3.4), negative likelihood ratio = 0.44(95% CI 0.26-0.75), diagnostic odds ratio = 6(95% CI 3-11), and SROC = 0.76(95% CI: 0.73-0.8). NLR could be diagnostic factor for the detection of potential VTE, the accuracy thereof in the current meta-analysis exhibited moderate accuracy for diagnosing VTE. Furthermore, further large cohort studies are needed to determine optimal cut-off values of NLR.

A Prediction Model Based on Blood Biomarker for Mortality Risk in Patients with Acute Venous Thromboembolism

Background

Most studies to date have focused on predicting the risk of venous thromboembolism (VTE), but prediction models about mortality risk in VTE are rarely reported. We sought to develop and validate a multivariable model to predict the all-cause mortality risk in patients with acute VTE in emergency settings.

Methods

A total of 700 patients were included from Qilu Hospital of Shandong University and were randomly assigned into training set (n=490) and validation set (n=210) in an 7:3 ratio. Multivariate logistics regression analysis was performed to identify independent variables and develop a prediction model, which was validated internally using bootstrap method. The discrimination, calibration and clinical utility were evaluated by receiver operating characteristic curve (ROC) analysis, Hosmer-Lemeshow (HL) test, Kaplan-meier (KM) analysis and decision curve analysis (DCA).

Results

There were 52 patients (10.6%) dying and 437 (89.4%) surviving in training set. Age (odds ratio [OR]: 4.158, 95% confidence interval [CI]: 2.426–7.127), pulmonary embolism (OR: 1.779, 95% CI: 1.124–2.814), platelet count (OR: 0.507, 95% CI: 0.310–0.830), D-dimer (OR: 1.826, 95% CI: 1.133–2.942) and platelet/lymphocyte ratio (OR: 2.166, 95% CI: 1.259–3.727) were independent risk variables associated with all-cause mortality. The model had good predictive capability with an AUC of 0.746 (95% CI: 0.668,0.825), a sensitivity of 0.769 (95% CI: 0.607,0.889), a specificity of 0.672 (95% CI: 0.634,0.707). The validation model had an AUC of 0.739 (95% CI: 0.685,0.793), a sensitivity of 0.690 (95% CI: 0.580,0.787), a specificity of 0.693 (95% CI: 0.655,0.729). The model is well calibrated and the HL test showed a good fit (χ²=5.291, p=0.726, Nagelkerke R²=0.137). KM analysis and DCA showed a good clinical utility of the nomogram.

Conclusion

This study identified independent variables affecting all-cause mortality in patients with acute VTE, and developed a prediction model and provided a nomogram with good prediction capability and clinical utility.

Preclinical Evaluation of Fingolimod in Rodent Models of Stroke With Age or Atherosclerosis as Comorbidities

Preclinical data indicate that fingolimod improves outcome post-ischaemia. This study used a rigorous study design in normal male C57BL/6JOlaHsd mice and in mice with common stroke comorbidities to further evaluate the translational potential of fingolimod. Stroke was induced via middle cerebral artery electrocoagulation in 8–9-week old mice (young mice), 18 month old mice (aged mice), and in high-fat diet-fed 22-week old ApoE−/− mice (hyperlipidaemic mice). Recovery was evaluated using motor behavioural tests 3 and 7 days after stroke. Tissue damage was evaluated at 7 days. A lower dose of fingolimod, 0.5 mg/kg, but not 1 mg/kg, increased lesion size but decreased ipsilateral brain atrophy in younger mice, without an effect on behavioural outcomes. Fingolimod-treated aged mice showed a significant improvement over saline-treated mice in the foot fault test at 7 days. Fingolimod-treated hyperlipidaemic mice showed a decreased infarct size but no difference in behavioural performance. Increasing fingolimod treatment time to 10 days showed no benefit in young mice. Pooled data showed that fingolimod improved performance in the foot fault test. Flow cytometry studies showed that fingolimod had marked effects on T cell frequencies in various tissues. The results show that the effects of fingolimod in stroke are less robust than the existing literature might indicate and may depend on the inflammatory status of the animals.

Inflammatory factors driving atherosclerotic plaque progression new insights

Coronary atherosclerosis is a chronic inflammatory disease that can lead to varying degrees of blood flow obstruction and a common pathophysiological basis of cardiovascular disease. Inflammatory factors run through the whole process of atherosclerotic lesions. Macrophages, T cells, and neutrophils play important roles in the process of atherosclerotic inflammation. Considering the evolutionary characteristics, atherosclerosis can be divided into different stages as early atherosclerotic plaque, plaque formation stage, and plaque rupture stage. In this paper, the changes in inflammatory cells at different stages of lesions and their related mechanisms are discussed, which can provide new insights from a clinical to bench perspective for atherosclerosis me chanism.

Gut Dysbiosis and Immune System in Atherosclerotic Cardiovascular Disease (ACVD)

Atherosclerosis is a leading cause of cardiovascular disease and mortality worldwide. Alterations in the gut microbiota composition, known as gut dysbiosis, have been shown to contribute to atherosclerotic cardiovascular disease (ACVD) development through several pathways. Disruptions in gut homeostasis are associated with activation of immune processes and systemic inflammation. The gut microbiota produces several metabolic products, such as trimethylamine (TMA), which is used to produce the proatherogenic metabolite trimethylamine-N-oxide (TMAO). Short-chain fatty acids (SCFAs), including acetate, butyrate, and propionate, and certain bile acids (BAs) produced by the gut microbiota lead to inflammation resolution and decrease atherogenesis. Chronic low-grade inflammation is associated with common risk factors for atherosclerosis, including metabolic syndrome, type 2 diabetes mellitus (T2DM), and obesity. Novel strategies for reducing ACVD include the use of nutraceuticals such as resveratrol, modification of glucagon-like peptide 1 (GLP-1) levels, supplementation with probiotics, and administration of prebiotic SCFAs and BAs. Investigation into the relationship between the gut microbiota, and its metabolites, and the host immune system could reveal promising insights into ACVD development, prognostic factors, and treatments.

Neutrophil to Lymphocyte Ratio (NLR) as an Easily Accessible Parameter for Monitoring Tacrolimus Overdose after Heart Transplantation—Experimental Study

(1) Background: The combination of candidate selection, immunosuppressive therapy adjustment, and scrutinous monitoring is a cornerstone for optimizing long-term survival after a heart transplant. Neutrophil-to-lymphocyte ratio (NLR) is a simple marker of inflammatory reactions activation and may play a clinical role as a predictive marker in oncological and cardiovascular diseases. The aim of the study was to find simple hematologic indices available from whole blood count to help in immunosuppressive therapy monitoring. (2) Methods: Thirty patients (23 men and 7 women) with a mean age of 43 +/− 13 years who had undergone orthotopic heart transplantation were enrolled into the study. The blood samples for whole blood count and Tacrolimus level were collected during outpatient visits in heart transplant recipients every two months for 18 months after first year post transplantation. (3) Results: There was a significant correlation between Tacrolimus overdose (>15 ng/mL) and NLR (Spearman’s rho 0.99, p < 0.001) and mean platelet volume (Spearman’s rho 0.989, p < 0.001). The ROC analysis for NLR above 3.62 showed predictive properties for Tacrolimus overdose (over 15 ng/mL) (AUC =0.633, p = 0.008) with a sensitivity of 50% and specificity of 83.73%. (4) Conclusions: Our results suggest that NLR above 3.62 may be regarded as a simple indicator of tacrolimus overdose.

Diagnostic and Prognostic Value of Immune/Inflammation Biomarkers for Venous Thromboembolism: Is It Reliable for Clinical Practice?

Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), has been an important cause of sudden in-hospital death. Studies have shown that the immune/inflammatory response plays an important role in the pathogenesis of vascular disease, with representative markers in the blood including the neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), systemic immune/inflammatory index (SII), etc. However, there is a variety of immune/inflammatory indicators. Moreover, most previous studies have been single-center investigations involving one or two indicators, with varying nature of cases, number of cases and study objectives, thereby making it difficult to reach consensus conclusions with good clinical guidelines. This article reviews the clinical value of immunoinflammatory indicators for VTE based on previous studies, including the diagnostic and prognostic capabilities. In conclusion, NLR provides promising predictive capability for the onset and prognosis of VTE and deserves extensive application in clinical practice. PLR also has certain diagnostic and prognostic value, but further studies are warranted to identify its reliability and stability. Monocytes, eosinophils and platelet-related indicators show some clinical association with VTE, although the predictive capabilities are mediocre. SII is of promising potential value for VTE and deserves further investigations. This review will provide new clues and valuable clinical guidance for the diagnosis and therapy of VTE.

Cardiovascular disease in systemic lupus erythematosus

There is a well-known increased risk for cardiovascular disease that contributes to morbidity and mortality in systemic lupus erythematosus (SLE). Major adverse cardiovascular events and subclinical atherosclerosis are both increased in this patient population. While traditional cardiac risk factors do contribute to the increased risk that is seen, lupus disease-related factors, medications, and genetic factors also impact the overall risk. SLE-specific inflammation, including oxidized lipids, cytokines, and altered immune cell subtypes all are likely to play a role in the pathogenesis of atherosclerotic plaques. Research is ongoing to identify biomarkers that can help clinicians to predict which SLE patients are at the greatest risk for cardiovascular disease (CVD). While SLE-specific treatment regimens for the prevention of cardiovascular events have not been identified, current strategies include minimization of traditional cardiac risk factors and lowering of overall lupus disease activity.

Immunological features beyond CD4/CD8 ratio values in older individuals

The CD4/CD8 T-cell ratio is emerging as a relevant marker of evolution for many pathologies and therapies. We aimed to explore immunological features beyond CD4/CD8 ratio values in older subjects (>65 years old) who were classified as having lower (<1.4), intermediate (1.4-2), or higher (>2) ratio values. The lower group showed a lower thymic output (sj/β-TREC ratio) and frequency of naïve T-cells, concomitant with increased mature T-cells. In these subjects, the CD4 T-cell subset was enriched in CD95+ but depleted of CD98+ cells. The regulatory T-cell (Treg) compartment was enriched in CTLA-4+ cells. The CD8 T-cell pool exhibited increased frequencies of CD95+ cells but decreased frequencies of integrin-β7+ cells. Interestingly, in the intermediate group, the CD4 pool showed greater differences than the CD8 pool, mostly for cellular senescence. Regarding inflammation, only hsCRP was elevated in the lower group; however, negative correlations between the CD4/CD8 ratio and β2-microglobulin and sCD163 were detected. These subjects displayed trends of more comorbidities and less independence in daily activities. Altogether, our data reveal different thymic output and immune profiles for T-cells across CD4/CD8 ratio values that can define immune capabilities, affecting health status in older individuals. Thus, the CD4/CD8 ratio may be used as an integrative marker of biological age.

Adaptive immune disorders in hypertension and heart failure: focusing on T-cell subset activation and clinical implications

: Hypertension is a growing health concern worldwide. Established hypertension is a causative factor of heart failure, which is characterized by increased vascular resistance and intractable uncontrolled blood pressure. Hypertension and heart failure have multiple causes and complex pathophysiology but cellular immunity is thought to contribute to the development of both. Recent studies showed that T cells play critical roles in hypertension and heart failure in humans and animals, with various stimuli leading to the formation of effector T cells that infiltrate the cardiovascular wall. Monocytes/macrophages also accumulate in the cardiovascular wall. Various cytokines (e.g. interleukin-6, interleukin-17, interleukin-10, tumor necrosis factor-α, and interferon-γ) released from immune cells of various subtypes promote vascular senescence and elastic laminal degradation as well as cardiac fibrosis and/or hypertrophy, leading to cardiovascular structural alterations and dysfunction. Recent laboratory evidence has defined a link between inflammation and the immune system in initiation and progression of hypertension and heart failure. Moreover, cross-talk among natural killer cells, adaptive immune cells (T cells and B cells), and innate immune cells (i.e. monocytes, macrophages, neutrophils, and dendritic cells) contributes to end-cardiovasculature damage and dysfunction in hypertension and heart failure. Clinical and experimental studies on the diagnostic potential of T-cell subsets revealed that blood regulatory T cells, CD4 cells, CD8 T cells, and the ratio of CD4 to CD8 T cells show promise as biomarkers of hypertension and heart failure. Therapeutic interventions to suppress activation of these cells may prove beneficial in reducing end-organ damage and preventing consequences of cardiovascular failure, including hypertension of heart failure.

Dendritic Cells and T Cells, Partners in Atherogenesis and the Translating Road Ahead

Atherosclerosis is a chronic process associated with arterial inflammation, the accumulation of lipids, plaque formation in vessel walls, and thrombosis with late mortal complications such as myocardial infarction and ischemic stroke. Immune and inflammatory responses have significant effects on every phase of atherosclerosis. Increasing evidence has shown that both innate and adaptive “arms” of the immune system play important roles in regulating the progression of atherosclerosis. Accumulating evidence suggests that a unique type of innate immune cell, termed dendritic cells (DCs), play an important role as central instigators, whereas adaptive immune cells, called T lymphocytes, are crucial as active executors of the DC immunity in atherogenesis. These two important immune cell types work in pairs to establish pro-atherogenic or atheroprotective immune responses in vascular tissues. Therefore, understanding the role of DCs and T cells in atherosclerosis is extremely important. Here, in this review, we will present a complete overview, based on existing knowledge of these two cell types in the atherosclerotic microenvironment, and discuss some of the novel means of targeting DCs and T cells as therapeutic tactics for the treatment of atherosclerosis.

Leukocyte Traits and Exposure to Ambient Particulate Matter Air Pollution in the Women's Health Initiative and Atherosclerosis Risk in Communities Study

BACKGROUND

Inflammatory effects of ambient particulate matter (PM) air pollution exposures may underlie PM-related increases in cardiovascular disease risk and mortality, although evidence of PM-associated leukocytosis is inconsistent and largely based on small, cross-sectional, and/or unrepresentative study populations.

OBJECTIVES

Our objective was to estimate PM-leukocyte associations among U.S. women and men in the Women's Health Initiative and Atherosclerosis Risk in Communities study (n = 165,675 ).

METHODS

We based the PM-leukocyte estimations on up to four study visits per participant, at which peripheral blood leukocytes and geocoded address-specific concentrations of PM ≤ 10 , ≤ 2.5 , and 2.5 - 10 μ m in diameter (PM 10 , PM 2.5 , and PM 2.5 - 10 , respectively) were available. We multiply imputed missing data using chained equations and estimated PM-leukocyte count associations over daily to yearly PM exposure averaging periods using center-specific, linear, mixed, longitudinal models weighted for attrition and adjusted for sociodemographic, behavioral, meteorological, and geographic covariates. In a subset of participants with available data (n = 8,457 ), we also estimated PM-leukocyte proportion associations in compositional data analyses.

RESULTS

We found a 12   cells / μ L (95% confidence interval: - 9 , 33) higher leukocyte count, a 1.2% (0.6%, 1.8%) higher granulocyte proportion, and a - 1.1 % (- 1.9 % , - 0.3 % ) lower CD 8 + T-cell proportion per 10 - μ g / m 3 increase in 1-month mean PM 2.5 . However, shorter-duration PM 10 exposures were inversely and only modestly associated with leukocyte count.

DISCUSSION

The PM 2.5 -leukocyte estimates, albeit imprecise, suggest that among racially, ethnically, and environmentally diverse U.S. populations, sustained, ambient exposure to fine PM may induce subclinical, but epidemiologically important, inflammatory effects. https://doi.org/10.1289/EHP5360.

Vascular Diseases and Gangliosides

Vascular diseases, such as myocardial infarction and cerebral infarction, are most commonly caused by atherosclerosis, one of the leading causes of death worldwide. Risk factors for atherosclerosis include lifestyle and aging. It has been reported that lifespan could be extended in mice by targeting senescent cells, which led to the suppression of aging-related diseases, such as vascular diseases. However, the molecular mechanisms underlying the contribution of aging to vascular diseases are still not well understood. Several types of cells, such as vascular (endothelial cell), vascular-associated (smooth muscle cell and fibroblast) and inflammatory cells, are involved in plaque formation, plaque rupture and thrombus formation, which result in atherosclerosis. Gangliosides, a group of glycosphingolipids, are expressed on the surface of vascular, vascular-associated and inflammatory cells, where they play functional roles. Clarifying the role of gangliosides in atherosclerosis and their relationship with aging is fundamental to develop novel prevention and treatment methods for vascular diseases based on targeting gangliosides. In this review, we highlight the involvement and possible contribution of gangliosides to vascular diseases and further discuss their relationship with aging.