Quantitative Analysis of Innate Lymphoid Cells in Patients with ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Acute myocardial infarction (AMI) is one of the principal causes of death in Mexico and worldwide. AMI triggers an acute inflammatory process that induces the activation of different populations of the innate immune system. Innate lymphoid cells (ILCs) are an innate immunity, highly pleiotropic population, which have been observed to participate in tissue repair and polarization of the adaptive immune response. OBJECTIVE: We aimed to analyze the levels of subsets of ILCs in patients with ST-segment elevation myocardial infarction (STEMI), immediately 3 and 6 months post-AMI, and analyze their correlation with clinical parameters. RESULTS: We evaluated 29 STEMI patients and 15 healthy controls and analyzed the different subsets of circulating ILCs, immediately 3 and 6 months post-AMI. We observed higher levels of circulating ILCs in STEMI patients compared to control subjects and a significant correlation between ILC levels and cardiac function. We also found increased production of the cytokines interleukin 5 (IL-5) and interleukin 17A (IL-17A), produced by ILC2 cells and by ILC3 cells, respectively, in the STEMI patients. CONCLUSION: This study shows new evidence of the role of ILCs in the pathophysiology of AMI and their possible involvement in the maintenance of cardiac function.

Immunoglobulin E Sensitization to Mammalian Oligosaccharide Galactose-α-1,3 (α-Gal) Is Associated With Noncalcified Plaque, Obstructive Coronary Artery Disease, and ST-Segment-Elevated Myocardial Infarction.

BACKGROUND: Treating known risk factors for coronary artery disease (CAD) has substantially reduced CAD morbidity and mortality. However, a significant burden of CAD remains unexplained. Immunoglobulin E sensitization to mammalian oligosaccharide galactose-α-1,3-galactose (α-Gal) was recently associated with CAD in a small observational study. We sought to confirm that α-Gal sensitization is associated with CAD burden, in particular noncalcified plaque. Additionally, we sort to assess whether that α-Gal sensitization is associated with ST-segment-elevated myocardial infarction (STEMI) Methods: We performed a cross-sectional analysis of participants enrolled in the BioHEART cohort study. We measured α-Gal specific-immunoglobulin E antibodies in serum of 1056 patients referred for CT coronary angiography for suspected CAD and 100 selected patients presenting with STEMI, enriched for patients without standard modifiable risk factors. CT coronary angiograms were assessed using coronary artery calcium scores and segmental plaque scores. RESULTS: α-Gal sensitization was associated with presence of noncalcified plaque (odds ratio, 1.62 [95% CI, 1.04-2.53], P=0.03) and obstructive CAD (odds ratio, 2.05 [95% CI, 1.29-3.25], P=0.002), independent of age, sex, and traditional risk factors. The α-Gal sensitization rate was 12.8-fold higher in patients with STEMI compared with matched healthy controls and 2.2-fold higher in the patients with STEMI compared with matched stable CAD patients (17% versus 1.3%, P=0.01 and 20% versus 9%, P=0.03, respectively). CONCLUSIONS: α-Gal sensitization is independently associated with noncalcified plaque burden and obstructive CAD and occurs at higher frequency in patients with STEMI than those with stable or no CAD. These findings may have implications for individuals exposed to ticks, as well as public health policy. Registration: URL: https://www.anzctr.org.au; Unique identifier: ACTRN12618001322224.

Impact of Age on Systemic Inflammatory Profile of Patients With ST-Segment-Elevation Myocardial Infarction and Acute Ischemic Stroke.

BACKGROUND: Aging is associated with a chronic low-grade inflammatory state. This condition may affect the acute inflammatory response involved in ST-segment-elevation myocardial infarction (STEMI) or acute ischemic stroke (AIS). We sought to compare the profile of a set of circulating inflammatory markers between young and older patients admitted for STEMI or AIS. METHODS: HIBISCUS-STEMI (Cohort of Patients to Identify Biological and Imaging Markers of Cardiovascular Outcomes in ST Elevation Myocardial Infarction) and HIBISCUS-STROKE (Cohort of Patients to Identify Biological and Imaging Markers of Cardiovascular Outcomes in Stroke) are 2 cohort studies that enrolled patients with STEMI treated with primary percutaneous coronary intervention in the cardiac intensive care unit of Lyon and patients with AIS treated with mechanical thrombectomy in the Lyon Stroke Center, respectively from 2016 to 2019. Patients were classified as older if they were ≥65 years and as young if they were <65 years. In both cohorts, CRP (C-reactive protein), IL (interleukin)-6, IL-8, IL-10, MCP (monocyte chemoattractant protein), sTNF-RI (soluble tumor necrosis factor receptor I), sST2 (soluble form suppression of tumorigenicity 2), and VCAM-1 (vascular cellular adhesion molecule-1) were measured on serum collected at 5 time points using enzyme-linked immunosorbent assay. A multiple logistic regression model was performed to detect an association between area under the curve of circulating inflammatory markers within the first 48 hours and older age. RESULTS: A total of 260 patients with STEMI and 164 patients with AIS were included. Of them, there were 76 (29%) and 105 (64%) older patients with STEMI and AIS, respectively. Following multivariable analysis, a high area under the curve of IL-6 and sTNF-RI, a low lymphocyte count, and a high neutrophil-lymphocyte ratio at 24 hours were associated with older age in patients with STEMI and AIS. CONCLUSIONS: Older patients had higher IL-6 and sTFN-RI levels within the first 48 hours associated with a lower lymphocyte count and a higher neutrophil-lymphocyte ratio at 24 hours in both cohorts.

Unraveling the thread of uncontrolled immune response in COVID-19 and STEMI: an emerging need for knowledge sharing.

The outbreak of severe acute respiratory syndrome coronavirus 2 that first emerged in Wuhan in December 2019 has resulted in the devastating pandemic of coronavirus disease 2019, creating an emerging need for knowledge sharing. Meanwhile, myocardial infarction is and will probably remain the foremost cause of death in the Western world throughout the coming decades. Severe deregulation of the immune system can unnecessarily expand the inflammatory response and participate in target and multiple organ failure, in infection but also in critical illness. Indeed, the course and fate of inflammatory cells observed in severe ST-elevation myocardial infarction (neutrophilia, monocytosis, and lymphopenia) almost perfectly mirror those recently reported in severe coronavirus disease 2019. A pleiotropic proinflammatory imbalance hampers adaptive immunity in favor of uncontrolled innate immunity and is associated with poorer structural and clinical outcomes. The goal of the present review is to gain greater insight into the cellular and molecular mechanisms underlying this canonical activation and downregulation of the two arms of the immune response in both entities, to better understand their pathophysiology and to open the door to innovative therapeutic options. Knowledge sharing can pave the way for therapies with the potential to significantly reduce mortality in both infectious and noninfectious scenarios.

A DARPin targeting activated Mac-1 is a novel diagnostic tool and potential anti-inflammatory agent in myocarditis, sepsis and myocardial infarction.

The monocyte ß2-integrin Mac-1 is crucial for leukocyte-endothelium interaction, rendering it an attractive therapeutic target for acute and chronic inflammation. Using phage display, a Designed-Ankyrin-Repeat-Protein (DARPin) was selected as a novel binding protein targeting and blocking the αM I-domain, an activation-specific epitope of Mac-1. This DARPin, named F7, specifically binds to activated Mac-1 on mouse and human monocytes as determined by flow cytometry. Homology modelling and docking studies defined distinct interaction sites which were verified by mutagenesis. Intravital microscopy showed reduced leukocyte-endothelium adhesion in mice treated with this DARPin. Using mouse models of sepsis, myocarditis and ischaemia/reperfusion injury, we demonstrate therapeutic anti-inflammatory effects. Finally, the activated Mac-1-specific DARPin is established as a tool to detect monocyte activation in patients receiving extra-corporeal membrane oxygenation, as well as suffering from sepsis and ST-elevation myocardial infarction. The activated Mac-1-specific DARPin F7 binds preferentially to activated monocytes, detects inflammation in critically ill patients, and inhibits monocyte and neutrophil function as an efficient new anti-inflammatory agent.

Neutrophil extracellular traps and fibrocytes in ST-segment elevation myocardial infarction.

Leukocyte-mediated inflammation is central in atherothrombosis and ST-segment elevation myocardial infarction (STEMI). Neutrophil extracellular traps (NETs) have been shown to enhance atherothrombosis and stimulate fibroblast function. We analyzed the effects of NETs on cardiac remodeling after STEMI. We measured double-stranded (ds)DNA and citrullinated histone H3 (citH3) as NET surrogate markers in human culprit site and femoral blood collected during primary percutaneous coronary intervention (n = 50). Fibrocytes were characterized in whole blood by flow cytometry, and in culprit site thrombi and myocardium by immunofluorescence. To investigate mechanisms of fibrocyte activation, isolated NETs were used to induce fibrocyte responses in vitro. Enzymatic infarct size was assessed using creatine-phosphokinase isoform MB area under the curve. Left ventricular function was measured by transthoracic echocardiography. NET surrogate markers were increased at the culprit site compared to the femoral site and were positively correlated with infarct size and left ventricular dysfunction at follow-up. In vitro, NETs promoted fibrocyte differentiation from monocytes and induced fibrocyte activation. Highly activated fibrocytes accumulated at the culprit site and in the infarct transition zone. Our data suggest that NETs might be important mediators of fibrotic remodeling after STEMI, possibly by stimulating fibrocytes.

MerTK Cleavage on Resident Cardiac Macrophages Compromises Repair After Myocardial Ischemia Reperfusion Injury.

RATIONALE: Clinical benefits of reperfusion after myocardial infarction are offset by maladaptive innate immune cell function, and therapeutic interventions are lacking. OBJECTIVE: We sought to test the significance of phagocytic clearance by resident and recruited phagocytes after myocardial ischemia reperfusion. METHODS AND RESULTS: In humans, we discovered that clinical reperfusion after myocardial infarction led to significant elevation of the soluble form of MerTK (myeloid-epithelial-reproductive tyrosine kinase; ie, soluble MER), a critical biomarker of compromised phagocytosis by innate macrophages. In reperfused mice, macrophage Mertk deficiency led to decreased cardiac wound debridement, increased infarct size, and depressed cardiac function, newly implicating MerTK in cardiac repair after myocardial ischemia reperfusion. More notably, Mertk(CR) mice, which are resistant to cleavage, showed significantly reduced infarct sizes and improved systolic function. In contrast to other cardiac phagocyte subsets, resident cardiac MHCIILOCCR2- (major histocompatibility complex II/C-C motif chemokine receptor type 2) macrophages expressed higher levels of MerTK and, when exposed to apoptotic cells, secreted proreparative cytokines, including transforming growth factor-ß. Mertk deficiency compromised the accumulation of MHCIILO phagocytes, and this was rescued in Mertk(CR) mice. Interestingly, blockade of CCR2-dependent monocyte infiltration into the heart reduced soluble MER levels post-ischemia reperfusion. CONCLUSIONS: Our data implicate monocyte-induced MerTK cleavage on proreparative MHCIILO cardiac macrophages as a novel contributor and therapeutic target of reperfusion injury.

Immune-inflammatory response after bioresorbable vascular scaffold implantation in patients with acute myocardial infarction with ST elevation in a long-term perspective.

A higher rate of bioresorbable vascular scaffold (BVS) thrombosis has been observed after device implantation compared to implantation of permanent metallic stents in recently published studies. The mechanism of BVS thrombosis is currently under debate. To assess whether the immune-inflammatory response after BVS implantation is a potential trigger of BVS thrombosis. The PRAGUE-19 study was an academic study that enrolled consecutive patients with ST-segment elevation myocardial infarction (STEMI) with the intention to implant a BVS. A laboratory sub-study included 49 patients with an implanted BVS (of which 38 underwent the complete 2-year follow-up) and 52 patients having an implanted permanent metallic stent as the control group (of which 30 underwent the complete 2-year follow-up). Samples for inflammatory markers [high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α)] were taken before BVS or stent implantation, on days 1 and 2 after device implantation and at 1 month and 2 years for a clinical control. The primary combined clinical endpoint of the sub-study (death, reinfarction or target vessel revascularization) occurred in 4.08% of the BVS group and 7.69% of the control group (p = 0.442) during the 2-year follow-up period, with overall mortality of 2.04% in the BVS group and 1.92% in the control group (p = 0.966). Definite BVS thrombosis occurred in one patient in the subacute phase; there was no late or very late thrombosis. Two definite stent thromboses were observed in the control group: one in the subacute phase and the other in the late phase. Baseline inflammatory marker levels did not differ between the groups. Lower levels of IL-6 and hs-CRP were observed in the BVS group compared to the control group (12.02 ± 5.94 vs. 15.21 ± 5.33 pg/ml; p < 0.01; 3952.9 ± 1704.75 ng/ml vs. 4507.49 ± 1190.01 ng/ml; p = 0.037, respectively) on days 1 and 2 (12.01 ± 6.31 vs. 13.85 ± 6.01 pg/ml; p = 0.089; 4447.92 ± 1325.31 ng/ml vs. 4637.03 ± 1290.99 ng/ml; p = 0.255, respectively). No differences in IL-6 or hs-CRP were observed after 1 month or 2 years in the clinical control. Levels of TNF-α did not differ between the groups in the early period after BVS or metallic stent implantation, nor during follow-up. The immune-inflammatory response is lower during the early phase after BVS implantation compared to that after metallic stent implantation, but the responses did not differ in the long term.

Effect of Oral N-Acetylcysteine Supplementation on the Immunity System in Patients with Acute Myocardial Infarction.

BACKGROUND: inflammation, oxidative stress, and fibrosis play important roles after an acute myocardial infarction (AMI) event. The most studied inflammatory biomarker in cardiovascular disease is C-reactive protein (CRP). It has been demonstrated that myeloperoxidase (MPO) and Galectin-3 (Gal-3) have some essential roles on immune system when an AMI event occurs. We aimed to determine the effect of oral N-acetylcysteine (NAC) supplementation at the dose of 600 mg 3 times daily for 3 consecutive days on the immune system of AMI patients. METHODS: our randomized single-blinded experimental study using pre- and post-treatment evaluations was performed at Dr. Moewardi Hospital, Indonesia, from May to August 2018. Thirty-two patients with AMI and ST segment elevation (STEMI) who received fibrinolytic therapy were included. There were 17 patients received standard therapy plus 600 mg oral NAC supplementation every 8 h for 3 days and 15 patients received standard therapy, which served as the control group. High-sensitivity C-reactive protein (HsCRP), MPO, and Gal-3 levels of both groups were evaluated at admission and after 72 h receiving treatment. RESULTS: HsCRP, MPO, and Gal-3 levels between NAC and control groups at admission were not significantly different; while intergroup differences after 72 h of NAC supplementation were significant (p values of HsCRP, MPO, and Gal-3 levels were 0.0001, 0.001, and 0.017, respectively). Furthermore, in the NAC group, HsCRP, MPO, and Gal-3 levels at 72 h after treatment were significantly different from the corresponding levels at admission (p values: 0.0001, 0.0001, and 0.0001, respectively); the control group did not show these differences. There were also significant intergroup differences between the NAC and control groups regarding HsCRP, MPO, and Gal-3 levels (p values: 0.011, 0.022, and 0.014, respectively). CONCLUSION: oral supplementation of 600 mg NAC every 8 h for 72 h can reduce HsCRP, MPO, and Gal-3 levels in AMI patients receiving fibrinolytic therapy. Results of our study will provide more options for supplementation therapy to improve management of IMA patients.

L5-LDL from ST-elevation myocardial infarction patients induces IL-1ß production via LOX-1 and NLRP3 inflammasome activation in macrophages.

L5-LDL, the most electronegative LDL associated with major cardiovascular risks, significantly rises in patients with ST-segment elevation myocardial infarction (STEMI). The inflammatory nature of atherosclerotic vascular diseases has prompted us to investigate whether L5-LDL induces the production of inflammatory cytokines, especially vascular ischemia-related interleukin (IL)-1ß, in the pathogenesis of STEMI. Clinical data showed that plasma levels of L5-LDL and IL-1ß were higher in the STEMI patients than in the controls (P < 0.05). In THP-1-derived human macrophages, L5-LDL significantly increased the levels of both IL-1ß and cleaved caspase-1, indicating the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasomes by L5-LDL. Knockdown of NLRP3 and its adaptor protein apoptosis-associated speck-like protein containing a CARD (ASC) resulted in decreased L5-LDL-induced IL-1ß. Furthermore, knock down of the lectin-type oxidized LDL receptor (LOX-1) in THP-1 cells attenuated L5-LDL-induced activation of NF-κB and caspase-1, leading to subsequent inhibition of IL-1ß in macrophages. Furthermore, blockade LOX-1 with neutralizing antibody also inhibited L5-LDL-induced IL-1ß in human peripheral blood mononuclear cell-derived macrophages. In conclusion, L5-LDL induces IL-1ß production in macrophages by activation of NF-κB and caspase-1 through the LOX-1-dependent pathway. This study represents the evidence linking L5-LDL and the inflammatory cytokine IL-1ß in STEMI, and identifies L5-LDL as a novel therapeutic target in acute myocardial infarction. NEW & NOTEWORTHY: This study represents the evidence linking L5-LDL and the inflammatory cytokine IL-1ß in ST-segment elevation myocardial infarction (STEMI). We elucidate the molecular mechanism underlying L5-LDL-induced production of IL-1ß in macrophages. The results showed that L5-LDL induced activation of caspase-1 and NF-κB through the lectin-type oxidized LDL receptor (LOX-1)-dependent pathway, leading to the production of IL-1ß.

Single-Cell Dissection of the Immune Response After Acute Myocardial Infarction.

BACKGROUND: The immune system's role in ST-segment-elevated myocardial infarction (STEMI) remains poorly characterized but is an important driver of recurrent cardiovascular events. While anti-inflammatory drugs show promise in reducing recurrence risk, their broad immune system impairment may induce severe side effects. To overcome these challenges, a nuanced understanding of the immune response to STEMI is needed. METHODS: For this, we compared peripheral blood mononuclear single-cell RNA-sequencing (scRNA-seq) and plasma protein expression over time (hospital admission, 24 hours, and 6-8 weeks post-STEMI) in 38 patients and 38 controls (95 995 diseased and 33 878 control peripheral blood mononuclear cells). RESULTS: Compared with controls, classical monocytes were increased and CD56dim natural killer cells were decreased in patients with STEMI at admission and persisted until 24 hours post-STEMI. The largest gene expression changes were observed in monocytes, associating with changes in toll-like receptor, interferon, and interleukin signaling activity. Finally, a targeted cardiovascular biomarker panel revealed expression changes in 33/92 plasma proteins post-STEMI. Interestingly, interleukin-6R, MMP9 (matrix metalloproteinase-9), and LDLR (low-density lipoprotein receptor) were affected by coronary artery disease-associated genetic risk variation, disease status, and time post-STEMI, indicating the importance of considering these aspects when defining potential future therapies. CONCLUSIONS: Our analyses revealed the immunologic pathways disturbed by STEMI, specifying affected cell types and disease stages. Additionally, we provide insights into patients expected to benefit most from anti-inflammatory treatments by identifying the genetic variants and disease stage at which these variants affect the outcome of these (drug-targeted) pathways. These findings advance our knowledge of the immune response post-STEMI and provide guidance for future therapeutic studies.

Systemic immune- inflammation index predicts post-MI left ventricular remodeling.

AIMS: Previous studies demonstrated that remodeling after successful percutaneous coronary intervention (PCI) depends on the inflammatory response triggered by myocardial infarction (MI). The systemic immune-inflammation index (SII) is a novel inflammation index strongly associated with coronary artery disease. In our study, we sought to determine whether SII could predict Post-MI LV remodeling. METHODS AND RESULTS: The study population included 528 patients (mean age 62.5 ± 10.2, 73% male) diagnosed with STEMI. Based on the increase in LVEDV within the first 12 months after STEMI, patients were divided into two groups. We categorized the ≥ 20% increase in LVEDV among remodelers (257 patients, 49%), and the other 271 patients (51%), as non-remodelers. To determine the relationship between laboratory parameters and LV remodeling, univariate and multivariate logistic regression models were used. In a univariate model, higher hs-CRP and SII values were associated with increased LVEDV. In a multivariate analysis, SII independently correlated with LV remodeling A cut-off value of 613.3 or higher for SII was significantly correlated with LV remodeling based on ROC analysis. CONCLUSION: SII provides an easy-to-calculate and affordable biomarker for cardiovascular diseases. It may be used as a new biomarker to predict LV remodeling in patients with STEMI.

Infliximab Limits Injury in Myocardial Infarction.

BACKGROUND: The purpose of this study was to investigate a therapeutic approach targeting the inflammatory response and consequent remodeling from ischemic myocardial injury. METHODS AND RESULTS: Coronary thrombus aspirates were collected from patients at the time of ST-segment-elevation myocardial infarction and subjected to array-based proteome analysis. Clinically indistinguishable at myocardial infarction (MI), patients were stratified into vulnerable and resilient on the basis of 1-year left ventricular ejection fraction and death. Network analysis from coronary aspirates revealed prioritization of tumor necrosis factor-α signaling in patients with worse clinical outcomes. Infliximab, a tumor necrosis factor-α inhibitor, was infused intravenously at reperfusion in a porcine MI model to assess whether infliximab-mediated immune modulation impacts post-MI injury. At 3 days after MI (n=7), infliximab infusion increased proregenerative M2 macrophages in the myocardial border zone as quantified by immunofluorescence (24.1%±23.3% in infliximab versus 9.29%±8.7% in sham; P<0.01). Concomitantly, immunoassays of coronary sinus samples quantified lower troponin I levels (41.72±7.34 pg/mL versus 58.11±10.75 pg/mL; P<0.05) and secreted protein analysis revealed upregulation of injury-modifying interleukin-2, -4, -10, -12, and -18 cytokines in the infliximab-treated cohort. At 4 weeks (n=12), infliximab treatment resulted in significant protective influence, improving left ventricular ejection fraction (53.9%±5.4% versus 36.2%±5.3%; P<0.001) and reducing scar size (8.31%±10.9% versus 17.41%±12.5%; P<0.05). CONCLUSIONS: Profiling of coronary thrombus aspirates in patients with ST-segment-elevation MI revealed highest association for tumor necrosis factor-α in injury risk. Infliximab-mediated immune modulation offers an actionable pathway to alter MI-induced inflammatory response, preserving contractility and limiting adverse structural remodeling.

Basophils balance healing after myocardial infarction via IL-4/IL-13.

The inflammatory response after myocardial infarction (MI) is a precisely regulated process that greatly affects subsequent remodeling. Here, we show that basophil granulocytes infiltrated infarcted murine hearts, with a peak occurring between days 3 and 7. Antibody-mediated and genetic depletion of basophils deteriorated cardiac function and resulted in enhanced scar thinning after MI. Mechanistically, we found that basophil depletion was associated with a shift from reparative Ly6Clo macrophages toward increased numbers of inflammatory Ly6Chi monocytes in the infarcted myocardium. Restoration of basophils in basophil-deficient mice by adoptive transfer reversed this proinflammatory phenotype. Cellular alterations in the absence of basophils were accompanied by lower cardiac levels of IL-4 and IL-13, two major cytokines secreted by basophils. Mice with basophil-specific IL-4/IL-13 deficiency exhibited a similarly altered myeloid response with an increased fraction of Ly6Chi monocytes and aggravated cardiac function after MI. In contrast, IL-4 induction in basophils via administration of the glycoprotein IPSE/α-1 led to improved post-MI healing. These results in mice were corroborated by the finding that initially low counts of blood basophils in patients with acute MI were associated with a worse cardiac outcome after 1 year, characterized by a larger scar size. In conclusion, we show that basophils promoted tissue repair after MI by increasing cardiac IL-4 and IL-13 levels.

Overexpression of genes involved in lymphocyte activation and regulation are associated with reduced CRM-derived cardiac remodelling after STEMI.

AIMS: Lymphopenia after ST-segment elevation myocardial infarction (STEMI) correlates with deleterious cardiac consequences and worse prognosis. An in-depth examination of genes implicated in lymphocyte proliferation, activation and regulation and their association with short- and long-term cardiac structure and function is therefore of great interest. METHODS: Peripheral blood mononuclear cells were isolated from 10 control subjects and 64 patients with a first STEMI treated with primary percutaneous coronary intervention and submitted to cardiac magnetic resonance after 1 week and 6 months. mRNA expression of genes implicated in lymphocyte activation (CD25 and CD69) and regulation [programmed death (PD)-1 and cytotoxic T-lymphocyte antigen (CTLA)-4] were determined by qRT-PCR. RESULTS: In comparison to controls, STEMI patients showed heightened mRNA expression of CD25 and lower PD-1 and CTLA-4 96 h after coronary reperfusion. Patients with extensive infarctions (>30% of left ventricular mass) at 1 week displayed a notable reduction in CD25, CD69, PD-1, and CTLA-4 expression (p < 0.05). However, CD25 was the only predictor of 1-week extensive infarct size in multivariate logistic regression analysis (odds ratio 0.019; 95% confidence interval [0.001-0.505]; p = 0.018). Regarding long-term ventricular function, mRNA expression of CD25 under the mean value was associated with worse ventricular function and more adverse remodelling. CONCLUSIONS: Following STEMI, heightened expression of genes expressed in regulatory T cells (CD25 and CD69) and immune checkpoints (PD-1 and CTLA-4) correlates with a better short- and long-term cardiac structure and function. Advancing understanding of the pathophysiology of lymphopenia and evaluating novel immunomodulatory therapies will help translate these results into future clinical trials.

Assessment of neutrophil and neutrophil/lymphocyte ratio in coronary collateral developed patients with acute coronary syndrome.

OBJECTIVE Inflammation-related markers provide diagnostic and prognostic information for coronary artery disease and acute coronary syndrome. We aimed to compare neutrophil count and neutrophil/lymphocyte ratio (NLR) in acute coronary syndrome patients with coronary collateral development in our study. METHODS A total of 426 patients (102 unstable angina pectoris (USAP), 223 non-ST-elevation myocardial infarction (non-STEMI), 103 ST-elevation myocardial infarction (STEMI) were compared regarding hemoglobin, platelet, lymphocyte, neutrophil count, and NLR. RESULTS Neutrophil count and NLR were significantly lower in USAP patients and higher in STEMI patients; 5.14± 1.79 vs. 7.21± 3.05 vs. 9.93±4.67 and 2.92±2.39 vs. 5.19±4.80 vs. 7.93±6.38, p <0.001. Other parameters, i.e., hemoglobin, platelet, and lymphocyte count, were not significantly different between the groups. CONCLUSIONS In our study, it was concluded that there may be a statistically significant difference in the number of neutrophil counts and NLR among the types of acute coronary syndromes with coronary collateral development.

Dynamic changes of innate lymphoid cells in acute ST-segment elevation myocardial infarction and its association with clinical outcomes.

An increasing body of evidence has implicated the innate immune system in the causation of acute ST-segment elevation myocardial infarction (STEMI). Innate lymphoid cells (ILCs) are newly identified members of the lymphoid lineage that are important effectors of innate immunity. The role of ILCs in STEMI has not been explored. We characterized the ILCs present in peripheral blood of 176 STEMI patients and 52 controls. Patients were followed up for up to 23 months. Flow cytometry showed that the proportion of total ILCs and ILC1s were significantly increased compared with controls; contrary to ILC1s, the proportion of ILC2s among total ILCs decreased significantly during the acute phase of STEMI. ILC1s percentage was an independent predictor of major adverse cardiovascular events (MACE). On multivariate Cox regression, the 3rd tertile of ILC1s was associated with a higher MACE rate compared with the 1st tertile (hazard ratio: 2.26; 95% confidence interval 1.56-3.27; P = 0.014). RNA-sequencing (RNA-Seq) revealed increased expressions of interferon-γ, tumor necrosis factor-α, vascular cell adhesion molecule 1 (VCAM1), and matrix metallopeptidase 9. Moreover, as active factors secreted by ILC1s, levels of interleukin (IL)-12 and IL-18 were significantly increased in STEMI patients. Increased ILC1s in patients with STEMI was associated with poor outcomes. Our findings suggest that ILC1s may play an important role in STEMI.

Admission Low-Density Lipoprotein Cholesterol Stratified by Circulating CD14++CD16+ Monocytes and Risk for Recurrent Cardiovascular Events Following ST Elevation Myocardial Infarction: Lipid Paradox Revised.

Lower level of low-density lipoprotein cholesterol (LDL-C) is paradoxically associated with increased mortality in ST elevation myocardial infarction (STEMI) patients. The underlying mechanism remains unclear. In a cohort of 220 de novo STEMI patients receiving timely primary percutaneous coronary intervention, admission LDL-C was negatively associated with circulating CD14++CD16+ monocyte counts. Moreover, admission LDL-C < 85 mg/dL was associated with increased risk for major adverse cardiovascular events (MACE) during a median follow-up of 2.7 years. After categorizing the patients according to the cutoff values of 85 mg/dL for LDL-C and the median for CD14++CD16+ monocytes, low LDL-C-associated MACE risk was only observed in those with high CD14++CD16+ monocyte counts (low LDL-C/high CD14++CD16+ monocytes vs. low LDL-C/low CD14++CD16+ monocytes: hazard ratio 5.38, 95% confidence interval 1.52 to 19.06, P = 0.009). This work provided the proof-of-principle evidence indicating a role of CD14++CD16+ monocytes in risk stratification of STEMI patients presenting with low LDL-C level. Graphical abstract.

Monocyte Subsets Are Differently Associated with Infarct Size, Left Ventricular Function, and the Formation of a Potentially Arrhythmogenic Scar in Patients with Acute Myocardial Infarction.

To investigate the role of classical (CLM, CD14++CD16-), intermediate (INTM, CD14++CD16+), and non-classical (Non-CLM, CD14+CD16++) monocytes in scar formation after ST-elevation myocardial infarction (STEMI), evaluated with cardiac magnetic resonance (CMR). One hundred two patients with a first STEMI had serial blood analyses after 1, 3, and 7 days. A CMR was performed at 7 days and 6 months, depicting scar core (CO), border zone (BZ), and the presence of BZ channels. CLM and INTM levels progressively decreased, correlated with the scar mass, CO, and BZ at 7 days and 6 months (p < 0.05), and inversely with left ventricular ejection fraction (LVEF, p < 0.01). Non-CLM levels gradually increased, correlated with BZ mass and the presence of BZ channels at 7 days and 6 months (p < 0.001).CLM and INTM are associated with infarct size and inversely with LVEF, whereas Non-CLM are associated with BZ mass and the presence of potentially arrhythmogenic substrate.