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Background Coronary no-reflow phenomenon in ST-segment elevation myocardial infarction (STEMI) is associated with a poor clinical prognosis. Although its pathophysiology is not fully elucidated, a deregulated systemic inflammatory response plays an important role. Specifically, the relationship between age-associated differences in inflammatory markers and either no-reflow or mortality in STEMI patients undergoing primary percutaneous coronary intervention (pPCI) has never been investigated. Methods and results We retrospectively enrolled 625 consecutive STEMI patients undergoing pPCI for whom a complete laboratory inflammatory pattern was available. Routinely blood measured laboratory parameters were collected at the moment of admission. No reflow was defined as Thrombolysis in Myocardial Infarction (TIMI) flow-grade lower than 3. The population was divided into two groups using a cut-off centered at 65 years. Compared to younger patients, elderly patients had higher mean values of fibrinogen, brain natriuretic peptide (BNP), leukocytes, neutrophil-to-lymphocyte ratio (NLR), C reactive protein/albumin ratio (CAR). Conversely, lymphocyte count and albumin levels were higher in young patients. In elderly patients, the values of NLR, CAR as well as leukocytes, fibrinogen and neutrophils were associated with no-reflow, while in young patients only BNP value was associated. At multivariate Cox regression analysis, only BNP and NLR resulted as independent predictors of all-cause mortality in the whole population and in elderly patients. Conclusions Elderly STEMI patients on admission had a higher acute pro-inflammatory profile than young patients, associated to coronary no-reflow and mortality outcome. These results suggest that a different therapeutic approach between elderly and young STEMI patients should be agreed.

Innate immune cells such as monocytes and macrophages are activated in response to microbial and other challenges and mount an inflammatory defensive response. Exposed cells develop the so-called innate memory, which allows them to react differently to a subsequent challenge, aiming at better protection. In this study, using human primary monocytes in vitro, we have assessed the memory-inducing capacity of two antigenic molecules of Schistosoma mansoni in soluble form compared to the same molecules coupled to outer membrane vesicles of Neisseria lactamica. The results show that particulate challenges are much more efficient than soluble molecules in inducing innate memory, which is measured as the production of inflammatory and anti-inflammatory cytokines (TNFα, IL-6, IL-10). Controls run with LPS from Klebsiella pneumoniae compared to the whole bacteria show that while LPS alone has strong memory-inducing capacity, the entire bacteria are more efficient. These data suggest that microbial antigens that are unable to induce innate immune activation can nevertheless participate in innate activation and memory when in a particulate form, which is a notion that supports the use of nanoparticulate antigens in vaccination strategies for achieving adjuvant-like effects of innate activation as well as priming for improved reactivity to future challenges.

Vascular and valvular calcification constitutes a major health problem with serious clinical consequences. It is important for medical laboratorians to improve their knowledge on this topic and to know which biological markers may have a potential interest and might be useful for diagnosis and for management of ectopic calcifications. This review focuses on the pathophysiological mechanisms of vascular and valvular calcification, with emphasis on the mechanisms that are different for the two types of events, which underscore the need for differentiated healthcare, and explain different response to therapy. Available imaging and scoring tools used to assess both vascular and valvular calcification, together with the more studied and reliable biological markers emerging in this field (e.g., Fetuin A and matrix Gla protein), are discussed. Recently proposed functional assays, measuring the propensity of human serum to calcify, appear promising for vascular calcification assessment and are described. Further advancement through omic technologies and statistical tools is also reported. Clinical chemistry and laboratory medicine practitioners overlook this new era that will engage them in the near future, where a close cooperation of professionals with different competencies, including laboratorists, is required. This innovative approach may truly revolutionize practice of laboratory and of whole medicine attitude, making progression in knowledge of pathways relevant to health, as the complex calcification-related pathways, and adding value to patient care, through a precision medicine strategy.

Background and Aims. Atherosclerosis is an inflammatory disease with long-lasting activation of innate immunity and monocytes are the main blood cellular effectors. We aimed to investigate monocyte phenotype (subset fraction and marker expression) at different stages of coronary atherosclerosis in stable coronary artery disease (CAD) patients. Methods. 73 patients with chronic coronary syndrome were evaluated by CT coronary angiography (CTCA) and classified by maximal diameter stenosis of major vessels into three groups of CAD severity: CAD1 (no CAD/minimal CAD, n°=30), CAD2 (non-obstructive CAD, n°=21), and CAD3 (obstructive CAD, n°=22). Flow cytometry for CD14, CD16, and CCR2 was used to quantify Mon1, Mon2, and Mon3 subsets. Expression of CD14, CD16, CD18, CD11b, HLA-DR, CD163, CCR2, CCR5, CX3CR1, and CXCR4 was also measured. Adhesion molecules and cytokines were quantified by ELISA. Results. Total cell count and fraction of Mon2 were higher in CAD2 and CAD3 compared to CAD1. By multivariate regression analysis, Mon2 cell fraction and Mon2 expression of CX3CR1, CD18, and CD16 showed a statistically significant and independent increase, parallel to stenosis severity, from CAD1 to CAD2 and CAD3 groups. A similar trend was also present for CX3CR1 and HLA-DR expressions on total monocyte population. A less calcified plaque composition was associated to a higher Mon2 expression of CD16 and higher TNF-α levels. IL-10 levels were lower at greater stenosis severity, while the IFN-γ/IL-10 ratio, a marker of a systemic pro-inflammatory imbalance, was directly correlated to stenosis degree and number of noncalcified plaques. Conclusions. The results of this study suggest that a specific pattern of inflammation-correlated monocyte marker expression is associated to higher stenosis severity and less calcified lesions in stable CAD. The clinical trial Identifier is NCT04448691.

Introduction: The increase of the anti-inflammatory CD163highHLA-DRlow blood monocyte subset is one of the mechanisms dampening inflammation during cardiac surgery with cardiopulmonary bypass. We evaluated the effect of two different anesthetic protocols, intravenous Propofol infusion or Sevoflurane-gas administration, on the perioperative frequency of this subset. Methods: Blood from patients (Propofol = 11, Sevoflurane = 13) undergoing minimally invasive mitral valve surgery was drawn preoperatively (T1), before declamping (T2), at 6 (T3), 24 (T4), 48 (T5), and 72 hours (T6) after declamping. C-reactive protein, haptoglobin, and lactate dehydrogenase were measured. A hemolytic index, as C-reactive protein/haptoglobin ratio, was introduced. Monocyte expression of HLA-DR, CD163, and the CD163highHLA-DRlow subset fraction was quantified by flow cytometry. Baseline-referred variations of plasmatic and cellular data at T2 were normalized for clamping times. Subsequent time-point variations were normalized for the final cardiopulmonary bypass times. Results: Variations of hemolytic index and lactate dehydrogenase were higher with Propofol at T3 (p = 0.004 and p = 0.02, respectively) when compared with Sevoflurane. At T2, the down-modulation of CD163 was higher with Propofol (p = 0.005). Starting from T3, the up-regulatory trend of CD163 was basically higher with Propofol, although not significantly. Propofol induced higher increments of HLA-DR low fractions, at T2 (p = 0.04) and, to a lesser extent, at T4 (p = 0.06). Starting from T3, the CD163highHLA-DRlow subset variations were higher with Propofol, especially at T4 and T6. Conclusion: Propofol seems to induce a higher postoperative fraction of the CD163highHLA-DRlow monocyte subset. This could represent either a compensatory mechanism dampening the higher inflammatory condition observed with Propofol at T2 or a consequence of a higher postoperative Propofol-induced hemolysis.

Introduction: Non-familial ascending thoracic aorta dilation and aneurysms (TAAs) are silent diseases in elderly patients. Histopathology revealed that functionally polarized infiltrating CD4+ T-cells play a key role in aortic wall weakening. Objective: To evaluate the possible associations between phenotype and cytokine production of circulating CD4+ T-lymphocytes and the presence of TAA in patients with aortic valve disease (AVD). Methods: We studied blood samples from 10 patients with TAA and 10 patients with AVD. Flow cytometry was used to quantify: a) CD4+ T-lymphocytes surface expression of CD25, CD28, and chemokine receptors (CCR5, CXCR3, CX3CR1); b) fractions of in vitro stimulated CD4+ T-cells producing cytokines (interferon gamma [IFN-γ], interleukin [IL]-17A, IL-21, IL-10); c) CD4+CD25highFoxP3+ regulatory T-cells (Treg) fraction. Enzyme-linked immunosorbent assays (ELISA) were performed for cytokines (IFN-γ, IL-6, IL-10, IL-17A, IL-23, transforming growth factor beta [TGF-β]) and chemokines (RANTES, CX3CL1). Results: The total CD4+CD28±CD4+/CX3CR1+ T-cells fraction was higher (P=0.0323) in AVD (20.452±4.673) than in TAA patients (8.633±2.030). The frequency ratio of CD4+ T-lymphocytes producing IFN-γ vs. IL-17A+IL-21 cytokine-producing CD4+ T-cells was higher (P=0.0239) in AVD (2.102±0.272) than in TAA (1.365±0.123) patients. The sum of CD4+CD28±CD4+/CX3CR1+ T-cells correlated positively with values of the previous cytokine ratio (P=0.0002, R=0.732). The ratio of CD4+CD28±CD4+/CX3CR1+ T-cells vs. Treg was higher (P=0.0008) in AVD (20.859±3.393) than in TAA (6.367±1.277) patients. Conclusion: Our results show that the presence of TAA in subjects with AVD is associated with imbalance between phenotypic and cytokine-producing subsets of circulating CD4+ T-lymphocytes, prevalently oriented towards a pro-fibrotic and IFN-γ counteracting effect to functional polarization.

Background & Objectives: Mortality and morbidity from the complication of aortic aneurysm remain very high. Aortic size index, which classify thoracic aortic aneurysm patients in three risk groups for aortic rupture prediction. Recent data support that aortic wall remodeling is a dynamic process with active involvement of the chronic inflammation and immunological system. Aim of our study is to evaluate expression level of chemokine receptors known to be involved in the T-cells migration and to correlate them with aortic size index. Materials & Methods: Total 20 patients undergoing surgery for ascending aortic aneurysm and/or aortic valve surgery were enrolled. Aortic size index was calculated. Preoperatively blood samples collected. By flowcytometry and dual parameter dot plot technology percentage of positivity of CCR5 on these T-cell subsets were quantified. Results: Mean age of the patients was 67±5.93 years. Majority of patients had hypertension. Mean ascending aortic diameter was 42.1±8.14 mm. Mean Aortic size Index was 22.21±3.38 mm/m2. A statistical significance has observed between aortic size index and the expression of CCR5 on total CD4 positive T-cells (p-0.0949), and between aortic size index and CCR5 expression on the total CD3 positive T-cells (p-0.0293). Significant correlation observed between ASI and CCR5 expression on the CD8+/CD3+ T-cell subset (p-0.0183). Similarly, strong positive relationship between ASI and the expression of CCR5 on the cytotoxic CD28-/CD4+ T-cell subset (p-0.0055). Activated state of cytotoxic CD28-/CD4+ cell also correlated with aortic size index (p-0.0668).Conclusion: We conclude that T-cell mediated cytotoxic mechanism driven by CCR5 play an important role in the pathophysiology of the thoracic aortic aneurysm.JCMS Nepal. 2016;12(1):23-27.

INTRODUCTION: Ascending thoracic aortic aneurysm (TAA) is a multi-factorial process in which histological modifications and immune-mediated inflammation are closely associated. The predominant role of a Th1-mediated response in influencing aortic wall remodeling, dilation, and aneurysm formation has been suggested by previous studies. Recently, the importance of chemokine receptors for Th1 cells recruitment into vascular inflammatory sites, as well as of the balance between pro- and anti-inflammatory T-cell subsets in influencing the severity of coronary artery disease, have been described.MATERIAL AND METHODS: We evaluated activation markers and chemokine receptors expression on peripheral T-cell and NK cell subsets of subject with aortic valve disease associated with ascending TAA (ascending aortic diameter > 4 cm) and undergoing elective surgery for TAA (Group A), in comparison with patients with aortic valve disease without TAA (ascending aortic diameter < 4 cm) (Group B). Peripheral blood samples from the two groups were also compared for intracellular T-lymphocyte cytokine production, frequency of regulatory T cells (Treg) and soluble levels of cytokine and chemokines. The aortic size index (ASI) was considered a parameter able to reflect aortic pathophysiological modifications leading to aortic dilation.RESULTS: The results demonstrated correlations between ASI values and CCR5 expression on CD3+, CD3+/CD8+, CD4+ and CD4+/CD28- T-cell subsets. In Group A the expression of CCR5 was higher on CD3+/CD8+, CD4+ and CD4+/CD28- T-cell subsets, when compared with Group B. CD4+ and CD4+/CD28- T-cells in Group A showed also a higher expression for the co-stimulatory molecule CD28 and the activation marker CD25, respectively. An increased expression of CXCR3 was found on CD4+, CD3+/CD8+ and CD3+/TCR+ T-cell subsets in Group A. A higher circulating fraction of NK cells, together with a higher NK cell positivity for CX3CR1, were observed in aneurysmatic patients. Intracellular cytokine analysis demonstrated a higher fraction of CD3+/CD4+ T-cells producing IL-17A and IL-10 in Group A, together with a higher intracellular content for IL-21. Finally, a higher soluble level of fractalkine (CX3CL1) has been detected in aneurysm group.CONCLUSION: Results indicate a higher activation state, migratory capacity and cytotoxic potential of peripheral blood NK and T-cell subsets in patients with aortic valve disease associated with ascending TAA, when compared with patients affected by aortic valve disease alone. These findings, together with the observed higher polarization towards a Th17 in patients with aortic aneurysm could suggest the involvement of autoimmune mechanisms leading to cellular loss, inflammation and fibrosis during ascending aortic wall dilation and aneurysmatic progression.Journal of Universal College of Medical Sciences Vol. 3, No. 1, 2015: 11-20

We investigated the ability of quercetin and apigenin to modulate platelet activation and aggregation, and compared the observed efficacy with that displayed by their synthetic analogues 2-phenyl-4H-pyrido[1,2-a]pyrimidin-4-ones, 1-4, and 2,3-diphenyl-4H-pyrido[1,2-a]pyrimidin-4-ones, 5-7. Platelet aggregation was explored through a spectrophotometric assay on platelet-rich plasma (PRP) treated with the thromboxane A2 mimetic U46619, collagen and thrombin in presence/absence of various bioisosteres of flavonoids (12.5-25-50-100 μM). The platelet density, (mean platelet component, MPC), was measured by the Advia 120 Hematology System as a marker surrogate of platelet activation. The induced P-selectin expression, which reflects platelet degranulation/activation, was quantified by flow cytometry on PRP. Our synthetic compounds modulated significantly both platelet activation and aggregation, thus turning out to be more effective than the analogues quercetin and apigenin when tested at a concentration fully consistent with their use in vivo. Accordingly, they might be used as food supplements to increase the efficacy of natural flavonoids.

As the endothelium still represents the ideal surface for cardiovascular devices, different endothelialization strategies have been attempted for biocompatibility and nonthrombogenicity enhancement. Since endothelial progenitor cells (EPCs) could accelerate endothelialization, preventing thrombosis and restenosis, the aim of this study was to use oligonucleotides (ONs) to biofunctionalize stents for EPC binding. In order to optimize the functionalization procedure before its application to cobalt-chromium (Co/Cr) stents, discs of the same material were preliminarily used. Surface aminosilanization was assessed by infrared spectroscopy and scanning electron microscopy. A fluorescent endothelial-specific ON was immobilized on aminosilanized surfaces and its presence was visualized by confocal microscopy. Fluorescent ON binding to porcine blood EPCs was assessed by flow cytometry. Viability assay was performed on EPCs cultured on unmodified, nontargeting ON or specific ON-coated discs; fluorescent staining of nuclei and F-actin was then performed on EPCs cultured on unmodified or specific ON-coated discs and stents. Disc biofunctionalization significantly increased EPC viability as compared to both unmodified and nontargeting ON-coated surfaces; cell adhesion was also significantly increased. Stents were successfully functionalized with the specific ON, and EPC binding was confirmed by confocal microscopy. In conclusion, stent biofunctionalization for EPC binding was successfully achieved in vitro, suggesting its use to obtain in vivo endothelialization, exploiting the natural regenerative potential of the human body.

Age-related cognitive impairment and dementia are an increasing societal burden. Epidemiological studies indicate that lifestyle factors, e.g. physical, cognitive and social activities, correlate with reduced dementia risk; moreover, positive effects on cognition of physical/cognitive training have been found in cognitively unimpaired elders. Less is known about effectiveness and action mechanisms of physical/cognitive training in elders already suffering from Mild Cognitive Impairment (MCI), a population at high risk for dementia. We assessed in 113 MCI subjects aged 65–89 years, the efficacy of combined physical-cognitive training on cognitive decline, Gray Matter (GM) volume loss and Cerebral Blood Flow (CBF) in hippocampus and parahippocampal areas, and on brain-blood-oxygenation-level-dependent (BOLD) activity elicited by a cognitive task, measured by ADAS-Cog scale, Magnetic Resonance Imaging (MRI), Arterial Spin Labeling (ASL) and fMRI, respectively, before and after 7 months of training vs. usual life. Cognitive status significantly decreased in MCI-no training and significantly increased in MCI-training subjects; training increased parahippocampal CBF, but no effect on GM volume loss was evident; BOLD activity increase, indicative of neural efficiency decline, was found only in MCI-no training subjects. These results show that a non pharmacological, multicomponent intervention improves cognitive status and indicators of brain health in MCI subjects.

The aim of the present work is to evaluate the in vitro immunocompatibility of an elastomeric material with feasible applications in the cardiovascular field. In particular, since it is well known that surface chemistry and topography play a key role in the foreign body response, their influence on human monocytes was evaluated. The material, constituted by a poly(ether)urethane (PEtU) and a polydimethylsiloxane (PDMS), was synthesized to manufacture films and small-diameter vascular grafts with three different surface topographical features, smooth, rough and porous, and siloxane rates, 10, 30 and 40. Human THP-1 monocytes have been cultured for 72 h on the films and human blood has been circulating for 2 h into the grafts to assess leukocyte adhesion and cytokine releases. Materials extracts were utilized to evaluate monocyte apoptosis. Smooth films showed lower cell adhesion degrees than rough and porous ones. All the PEtU-PDMS (poly(ether)urethane-polydimethylsiloxane) films and vascular grafts induced a narrow inflammatory response, as demonstrated by slight cytokine secretion levels, in particular samples with the highest PDMS contents (30 and 40%) induced the lowest IL-1b secretion. Moreover, an absence of monocyte apoptosis advises that the negligible release values have not to be ascribed to material toxicity. In the end, surface topography showed to affect only monocyte adhesion while siloxane content the cytokine release. Therefore, the possibility to modify the above tested parameters during material synthesis and manufacture could allow to bound the inflammatory potency of the PEtU-PDMS devices and render them excellent candidates for cardiovascular reconstruction.

Background: Platelet response to activating agents is used to monitor the efficacy of anti-aggregation therapies. The aim of our study has been to demonstrate the existence of relationships between early events of ADP-induced platelet activation, measured by flow cytometry and platelet-rich plasma aggregation, quantified by optical aggregometry. Methods: We evaluated peripheral blood of 12 donors. The following parameters were quantified by cytometry after stimulation with adenosine diphosphate (ADP) (0.5, 1, 2, 5, 10, 20 μM): CD62P (P-selectin) and PAC-1 expression, and cytosolic Ca2+ mobilization. Aggregation was measured by optical aggregometry. We also studied 13 patients, undergoing coronary stenting, treated with aspirin (before procedure) or with aspirin plus clopidogrel (after procedure). We evaluated CD62P and PAC-1 expression, aggregation, and vasodilator-stimulated phopshoprotein phosphorylation (platelet reactivity index, PRI). Results: Flow procedures were more sensitive than aggregometry, with a lowest interindividual variability. Linear relationships existed in donors between CD62P expression and Ca2+ mobilization (P < 0.0001), and between aggregation and Ca2+ mobilization (P < 0.0001). Linear relationships existed between aggregation and CD62P expression, as percentage (P < 0.0001), or relative fluorescence intensity (RFI) (P < 0.0001). Exponential equations related aggregation and PAC-1 expression, as percentage (P < 0.0001), or RFI (P < 0.0001). Linear relationships between aggregation and CD62P expression (as percentage) existed in the patients before (P = 0.0022) and after procedure (P = 0.0020). Exponential relationships between aggregation and PAC-1 expression (as percentage) existed before (P = 0.0012) and after procedure (P = 0.0024). Linear correlations related aggregation response predicted on CD62P expression, and measured aggregation inhibition after clopidogrel (P = 0.0013) as well as predicted aggregation and PRI inhibition (P = 0.0031). Conclusions: Tight relationships between aggregation and cytometric quantification of platelet markers in whole blood, in particular CD62P, allow to predict aggregation response to ADP from flow data in patients treated with aspirin alone or with aspirin plus clopidogrel. © 2007 Clinical Cytometry Society

An increasing amount of evidence indicates that platelet reactivity, despite a standard anti-thrombotic therapy, is a potential risk factor for recurrent myocardial ischemia in patients with coronary artery disease. We now hypothesize that this condition, measured by collagen-epinephrine (CEPI) or collagen-ADP (CADP) closure times (CT) by Platelet Function Analyzer (PFA-100), may predict the recurrence of coronary events after percutaneous coronary intervention (PCI).CEPI and CADP-CT were measured 30+/-8 h after PCI in 175 consecutive patients admitted with a diagnosis of stable angina (n=94) or acute coronary syndromes (n=81) and prospectively followed up for a mean period of 6 months. We stratified the patients in accordance to both the CEPI-CT (or190 s), reflecting the intensity of cycloxygenase inhibition by aspirin and the distribution into quartiles for CADP-CT.CEPI-CT190 s as well as CADP-CT82 s were associated with a higher rate of clinical recurrence (hazard ratio 8.5, p0.001 and 22.9, p0.001, respectively). Multivariate analysis after adjustment for other risk factors confirmed that the lowest CADP-CT quartile significantly correlates with the risk of recurrent coronary events (hazard ratio 36.5, p0.01), as well as CEPI-CT190 s (hazard ratio 6.7, p=0.01).An enhanced platelet function after PCI when measured under high shear rates by PFA-100 is an independent predictor of a worst clinical outcome, even during a short term follow-up and may help in patients risk stratification.

ObjectivesWe investigated the main biomolecular features in the evolution of aortic stenosis, focusing on advanced lesions.Background“Degenerative” aortic valve stenosis shares risk factors and inflammatory similarities with atherosclerosis.MethodsWe compared nonrheumatic stenotic aortic valves from 26 patients undergoing surgical valve replacement (group A) and 14 surgical control patients (group B). We performed semiquantitative histological and immunohistochemical analyses on valve leaflets to measure inflammation, sclerosis, calcium, neoangiogenesis, and intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression. We assessed heat shock protein 60 (hsp60) gene expression as an index of cellular stress and C-reactive protein, erythrocyte sedimentation rate, and fibrinogen as systemic inflammatory markers.ResultsIn group A valves, we found a prevalence of calcium nodules surrounded by activated inflammatory infiltrates, neovessels, and abundant ICAM-1, VCAM-1, and hsp60gene expression. Specimens from group B were negative for all of these markers, except 2 of 14 positivity for hsp60.The presence of active inflammatory infiltrates correlated with an abundance of thin neovessels (p < 0.01) and hsp60gene expression (p = 0.01), whereas neoangiogenesis correlated with inflammation (p = 0.04), calcium (p = 0.01), and hsp60gene expression (p = 0.04).Conclusions“Degenerative” aortic valve stenosis appears to be a chronic inflammatory process associated with atherosclerotic risk factors. The coexistence of neoangiogenesis, T-lymphocyte infiltration, adhesion molecules, and hsp60gene expression indicates an active immunomediated process in the final phases of the disease.

Cardiovascular surgery with cardiopulmonary bypass (CPB) induces activation of blood coagulation and systemic inflammation involved in post-operative complications. Our study evaluated the impact of the minimal extracorporeal circulation (mini-CPB) system (Synergy®, Sorin Group) on these functional aspects. Twenty patients were randomly assigned to standard CPB (n=10) or to Synergy (n=10). Platelet expression of PAC-1, and monocyte/granulocyte-platelet conjugates were evaluated by flow cytometry. A leukocyte-platelet adhesion index was calculated after cell number normalization. ELISAs were performed to measure IL-6 and TNF-α, thrombin-antithrombin III complexes (TAT), prothrombin fragments (F1+2), β-thromboglobulin (β-TG) and sP-selectin (sCD62P). Blood samples were drawn at the time of anesthesia (T1), at the end of CPB (T2), and at 4 (T3) and 24 hours (T4) after weaning from CPB. All patients were similar for clinical characteristics. When compared to standard CPB, the Synergy showed lower levels of the monocyte-platelet adhesion index at T2 (0.023 ± 0.005 vs 0.063 ± 0.013, P = 0.0092) and T4 (0.031 ± 0.003 vs 0.055 ± 0.005, P = 0.0017), TAT complexes at T2 (27.175 ± 5.967 vs 86.592 ± 5.415, P = 0.0005) and T3 (26.977 ± 2.468 vs 45.146 ± 4.365, P = 0.0041), F1+2 fragments at T2 (2.222 ± 0.226 vs 4.249 ± 0.292, P = 0.0009), and sP-selectin at T3 (115.17 ± 19.623 vs 169.554 ± 19.709, P = 0.0703) and T4 (108.542 ± 6.429 vs 140.799 ± 14.771, P = 0.0833). In summary, the Synergy exhibited a lower post-operative activation of blood coagulation, together with a reduced interaction between circulating monocytes and platelets.

Background: Neutrophil-granulocyte and mononuclear-cell functional changes occur during cardiopulmonary bypass and cardiovascular surgery. In particular, leukocyte–platelet interaction, leading to generation of heterotypic coaggregates, represents an amplification mechanism of the local inflammatory response and tissue damage. Methods: Samples of 20 patients were drawn from venous coronary sinus before cardioplegic arrest and immediately after reperfusion, as well as from peripheral blood at 5 and 24 h postoperatively. The granulocyte and monocyte surface expression of CD162, CD15s, CD18, and CD11b were quantified by flow cytometry at the different times. Parallel variations of circulating leukocyte–platelet conjugates (percentages) and a derived (cell number-normalized) leukocyte–platelet adhesion index were measured using a combination of antibodies against CD45, CD14, and CD41a. The evaluation of platelet functional state was carried out using antibodies against CD62P (P-selectin) and PAC-1. Results: Monocyte and granulocyte cell number increased markedly in coronary blood at reperfusion and in peripheral blood postoperatively when compared with measurements done before cardioplegia. A very different course characterized the changes of the leukocyte–platelet adhesion index with respect to the variations of circulating leukocyte–platelet coaggregates (percentages). Leukocyte molecules expression showed no significant variations for CD15s on both the leukocyte subsets, while a significant up-modulation for CD162 was observed on monocytes at 24 h after extracorporeal circulation (P = 0.0002), and for CD11b on granulocytes at 5 h postoperatively (P = 0.033). A loss of CD162 expression was observed in coronary blood at reperfusion (P = 0.0038) on granulocytes, associated to a down-modulation of CD18 (P = 0.0033) and CD11b (P = 0.0184) in peripheral blood at 24 h postoperatively. No significant up-regulation of platelet activatory molecules expression was found at coronary reperfusion, as well as postoperatively in the peripheral blood, when compared with the before-cardioplegia derived data. Conclusions: The over time variations of a normalized leukocyte–platelet adhesion index seem to reflect the cumulative leukocyte–platelet functional interaction more accurately than the parallel measurements of cellular conjugates. The absence of platelet activation suggests that the leukocyte membrane modifications play a main role in controlling the formation and stability of heterotypic leukocyte–platelet coaggregates after cardiac surgery with extracorporeal circulation. © 2006 International Society for Analytical Cytology

Background Distal protection devices have been shown to reduce the incidence of "no flow" phenomenon during primary percutaneous coronary intervention (PCI). So far, it has not been well clarified which mechanism is mainly involved in distal coronary protection. Aim To investigate the activation state of leukocytes and platelets locally present within the blood from the site of coronary occlusion. Methods Ten patients with acute myocardial infarction (AMI) underwent primary PCI with an embolization protection device and aspiration catheter (PercuSurge GuardWire) were included. The following functional parameters: a) monocyte and neutrophils surface molecules; b) platelet surface activatory antigens; c) leukocytes–platelet conjugates were studied by flow cytometry in blood obtained from the site of coronary occlusion and from peripheral femoral artery. Results The leukocyte–platelet adhesion index was significantly higher in the aspirated blood at the site of coronary occlusion than in the peripheral arterial blood for both monocytes (0.226±0.04 vs. 0.084±0.01; p =0.004) and neutrophils (1.372±0.3 vs. 0.524±0.1; p =0.02). Moreover, the volume of coaggregates exhibited a significant increase in coronary blood for both populations ( p =0.02 for monocytes and for neutrophils). Interestingly, a significant up-regulation of the adhesive molecule CD18 was observed in coronary blood respect to systemic circulation either in monocytes ( p =0.01) than in neutrophils ( p =0.003). A significant up-regulation of monocyte (HLA-DR) and neutrophil (CD66b) activatory molecules expression was also observed in the aspirated coronary compared to peripheral artery blood ( p =0.02 and p =0.03 for HLA-DR and CD66b, respectively). Conclusions These data indicate an increased leukocyte–platelet functional interaction in AMI at the site of plaque rupture relative to the systemic circulation, which may be one of the pathogenetic mechanisms responsible for myocardial "no-reflow" phenomenon.

An unsolved problem when employing small-diameter vascular grafts for aorto-coronary by-pass and peripheral reconstruction is the early thrombotic occlusion. The PEtU-PDMS is a new elastomeric material, composed of poly(ether)urethane and polydimethylsiloxane, synthesized to realize grafts with improved hemocompatibility characteristics. In order to investigate the effect of PDMS content on hemocompatibility, three different percentages of PDMS containing grafts (10, 25 and 40) were evaluated. Grafts realized with Estane 5714-F1 and silicone medical grade tubes were used as references. The hemocompatibility was investigated by an in vitro circuit in which human anticoagulated blood was circulated into grafts by a peristaltic pump modified to obtain a passive flow. For each experiment, 40 cm length graft was closed into a circular loop and put in rotation for 2 h at 37 degrees C. At the end of the experiments different parameters regarding platelet adhesion and activation were evaluated: circulating platelets count, beta-thromboglobulin release, platelet CD62P expression and amount of monocyte-platelet conjugates. PEtU-PDMS grafts with 25 and 40% of PDMS induced the lowest platelet adhesion, plasma level of beta-TG and amount of monocyte-platelet conjugates. No significative variations were observed in CD62P expression. In conclusion, PDMS content significatively affects blood-graft surface interaction, in fact higher PDMS percentage containing grafts showed the best in vitro hemocompatibility.

Background Neutrophil and mononuclear cell functional changes represent a hallmark of inflammation during cardiopulmonary bypass and cardiovascular surgery. Knowledge of mechanisms underlying monocyte functional modulation in coronary blood may be useful to develop protective interventions that can limit ischemia/reperfusion injury. Methods Samples of 13 patients were drawn from venous coronary sinus before cardioplegic arrest and after reperfusion. The following parameters were studied: surface molecules expression (CD18, CD11b, CD44, CD162, CD15s, CD80, CD86, CD16, CD49d, CD29, CD25, HLA-DR, Toll-like receptor-4 [TLR-4], CXCR1, CCR2, CCR5, CX3CR1), oxidative burst response, monocyte-platelet conjugates (using antibodies against CD45, CD14, CD41a), and platelet activation (CD62P, PAC-1). Enzyme-linked immunosorbent assays were performed to measure levels of interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor-α (TNF-α). Results Coronary reperfusion down-modulated monocyte molecules expression, especially for CD18 (P = 0.048), CD44 (P = 0.0035), CD49d (P = 0.0029), CD29 (P = 0.032), HLA-DR (P < 0.0001), TLR-4 (P = 0.0109), CCR2 (P = 0.0184), CCR5 (P = 0.0396), and CX3CR1 (P < 0.0001). A marginal increase (P = 0.062) of a normalized adhesion index between monocytes and platelets was observed at reperfusion. No variations were detected for the monocyte oxidative burst and platelet activation. Increased levels of IL-6 (P = 0.013), TNF-α (P = 0.0272), and IL-10 (P = 0.0008) were measured after cardioplegia. Conclusions The lack of CD11b and CD25 variations and of the oxidative burst exclude monocyte activation at reperfusion. The high after-cardioplegia level of IL-10, the decreased expression of HLA-DR and TLR-4, and the absence of IL-1β and IL-8 suggest an IL-10–mediated functional depression of monocyte, including their adhesive and migratory capacities. The lack of an after-cardioplegia orientation toward IL-10 producing a “macrophage-like” CD14+/CD16+ phenotype might mean that myocardial infiltrating lymphocytes are the main source of IL-10. Moreover, the increased after-cardioplegia levels of IL-6 and TNF-α might be due to myocardial and endothelial activations. The increased adhesion index between monocyte and platelets, without receptor variations, suggests a monocyte membrane modification induced by extracorporeal circulation. © 2005 Wiley-Liss, Inc.

Background Cardiovascular surgery with cardiopulmonary bypass (CPB) induces systemic inflammation and postoperative complications depending on pro- and anti-inflammatory mechanisms. Activated polymorphonuclear cells and monocytes may be responsible for morbidity associated with CPB. Knowledge of the monocyte functional state in particular may help to develop protective interventions. Methods Samples were drawn from venous peripheral blood (basal condition, at 4 and 24 h after CPB) and coronary blood (before and after cardioplegic arrest) of 14 patients undergoing cardiac surgery. The following phenotypic and functional parameters of the monocyte population were studied by flow cytometry: surface molecules expression (CD18, CD11a, CD11b, CD14, CD15, CD45, HLA-DR, and Toll-like receptor [TLR]-4), myeloperoxidase (MPO) content, and intracellular cytokine production (tumor necrosis factor [TNF]-α, interleukin [IL]-1β, IL-6, and IL-8). Results Cardiac surgery with CPB induced down-modulation of surface molecules expression on peripheral monocytes, especially at 24 h after CPB, for CD18, CD11a, and CD11b (P < 0.003) and for the CD15 adhesive cluster (P = 0.0028) and HLA-DR (P < 0.001). At 4 h after CPB, downregulation was observed for CD14 (P = 0.004), CD45 (P = 0.014), and CD15 (P = 0.0056). A loss of MPO was detected in venous peripheral (at 24 h after CPB, P = 0.01) or coronary (at reperfusion, P < 0.02) blood. The CD15 cluster complex exhibited a down-modulation in coronary blood (at reperfusion, P = 0.0003). Spontaneous intracellular production of IL-1β, IL-6, and IL-8 decreased at 24 h after CPB (P < 0.05). Conclusions The down-modulation of integrins and adhesive receptor expression and the loss of MPO suggest a strong activation and shedding reaction of circulating monocyte after CPB, further exacerbated by contact with coronary ischemic vessels. The changes of differentiation antigens may reflect the appearance of a partially immature population immediately after CPB. The reduced proinflammatory cytokine production, observed at 24 h after CPB, suggests a functional polarization of circulating monocytes. © 2003 Wiley-Liss, Inc.

Natural killer (NK) cells and dendritic cells (DCs) are two distinct cell types of innate immunity. It is known that the in vitro interaction of human NK cells with autologous DCs results in DC lysis. Here we show that contact-dependent interactions between activated human NK cells and immature DCs (iDCs) provides a “control switch” for the immune system. At low NK/DC ratios, this interaction dramatically amplifies DC responses, whereas at high ratios it completely turns off their responses. Specifically, culture of activated human NK cells with iDCs, at low NK/DC ratios (1:5), led to exponential increases in DC cytokine production, which were completely dependent on cell-to-cell contact. DC maturation was also driven by cognate interactions with NK cells and maturation was dependent on endogenously produced TNF-α in the culture. At slightly higher NK/DC ratios (5:1), inhibition of DC functions was the dominant feature due to potent killing by the autologous NK cells. Resting NK cells also stimulated autologous DC maturation in a TNF-α/contact-dependent manner, however, increasing the NK/DC ratio only led to an enhancement of this effect.

An apoptotic phenotype induced by oxygen radicals or Bax expression has been observed in Saccharomyces cerevisiae yeast cells by electron and fluorescence microscopy. In this work, we analyzed DNA content and cellular morphology of S. cerevisiae after H(2)O(2) or UV treatment by TdT-mediated dUTP nick end labeling (TUNEL)-test and flow cytofluorimetry. A TUNEL-positive phenotype was observed in both cases, on the same samples a dose-dependent increase in the sub-G(1) population was pointed out by flow cytometry. Sub-G(1) cells were isolated by flow sorting and analyzed by electron microscopy. This population showed condensed chromatin in the nucleus and cell shrinking. This paper reports the first evidence of apoptosis in yeast cells induced by DNA damage after UV irradiation.

Photodynamic therapy (PDT), a cancer treatment using a photosensitizer and visible light, has been shown to induce apoptosis or necrosis. We report here that Purpurin-18 (Pu18) in combination with light induces rapid apoptotic cell death in the human leukemia cell line (HL60) at low doses and necrosis at higher concentrations. Cells treated with Pu18 and light under apoptotic conditions exhibited DNA laddering and an increase in both cellular content of subdiploid DNA and externalization of phosphatidylserine (PS), indicating DNA fragmentation and loss of membrane phospholipid asymmetry. In the absence of light activation, Pu18 at nanomolar concentrations had no detectable cytotoxic effect. Caspase-3 activity was increased even after 1 h from treatment with low doses of Pu18 and light. The PS exposure and nuclear features of apoptosis were prevented by treatment of cells before illumination with caspase inhibitors benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK) and benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone (Z-DEVD-FMK). Conversely, the caspase-1 inhibitor, acetyl-Tyr-Val-Ala-Asp-aldehyde (Ac-YVAD-CHO) failed to suppress the apoptosis. No protective effect of the three caspase inhibitors was observed when the cells were exposed to necrotic concentrations of Pu18 and light. Our results show that caspase-3, but not caspase-1, is involved in the signaling of apoptotic events in PDT with Pu18-induced apoptosis of HL60 cells. Moreover, both the time course of PS exposure and the effect of caspase inhibitors on it indicate that it is regulated in the same manner as DNA fragmentation.

Combined L-lysine-L-arginine therapy is capable of inducting recovery in age-related decline of thymic activity in mice and in elderly humans. The clinical usefulness of the association has also been shown in children with recurrent respiratory infections, while an increase in the number of CD3+ lymphocytes has been shown in patients with chronic lymphatic leukaemia. Recently, in vitro effects of the association on neutrophil function have been reported. In particular, the association was able to increase random migration, chemotaxis, phagocytosis-associated- and f-MLP-induced chemiluminescence. In this paper the authors evaluate the effects of L-lysine-L-arginine combination (lisargin) on several humoral and cell-mediated immunologic parameters in patients with recurrent infection. An increase of neutrophil random migration and chemotaxis (evaluated by a new technique, based on a computer assisted image processing system) was found. Furthermore an increase in the absolute number of lymphocytes involved in cytotoxic activity and IgG levels was observed.

The effects of L-lysine, L-arginine, and lysine-arginine association on human neutrophil function were studied. The combination of the two agents, used at pharmacological concentrations, was able to increase both the phagocytosis-associated and the f-MLP-induced chemiluminescence, in the presence of luminol as amplifier agent. Neither superoxide anion production nor phytohaemagglutinin-induced aggregation were affected by the lysine-arginine association. The two amino-acids did not show any effect when used as single agents. L-canavanine (competitive inhibitor of nitric oxide synthesis starting from L-arginine) did not reduce chemiluminescence. These results show that the association lysine-arginine may increase the microbicidal potential of human neutrophils, probably by increasing the production of hypochlorous acid. In addition, a role for nitric oxide in these effects can be excluded.

Antibody response to antigen A60 (a mycobacterial antigen) was evaluated in ELISA in 18 HIV+ subjects with clinical and cultural evidences of mycobacterial infections, in 10 HIV+ subjects without Mycobacterial infections and in 22 healthy donors. We found higher levels of specific IgG in the HIV+ patients with Mycobacterial infections (mean 179.2 +/- 83 U) compared to the values of the donors (mean 92.5 +/- 35.5 U: p0.01). This test may be useful in the diagnosis of tuberculosis, but it needs clinical validation.

Six subjects (4 female, 2 male), aged from 16 to 25 years, presented with allergic rhinitis to Dermatophagoides mites and received SIT by the sub-cutaneous route with delayed-release alpha fraction Bayropharm at the standard doses. Diagnosis was based on clinical history, skin tests and measurement of specific IgE at 0, 3, 9, and 12 months, by the fluoro-enzymatic technique (FAST). For comparison, in a reference group (n = 20) the IgE varied between 0.32 and 0.11 IU/ml for D1 and 0.31 to 0.09 IU/ml for D2. The eight patients had specific IgE titres of D1 = 0.96, D2 = 0.99. For these authors, the FAST technique used for the measurement of specific IgE, although less sensitive than the RIA technique of RAST, gives a good evaluation of SIT.