Neutrophil Activation In Patients Research Articles

Statin Treatment Is Associated with Reduction in Serum Levels of Receptor Activator of NF-κB Ligand and Neutrophil Activation in Patients with Severe Carotid Stenosis

Systemic and intraplaque biomarkers have been widely investigated in clinical cohorts as promising surrogate parameters of cardiovascular vulnerability. In this pilot study, we investigated if systemic and intraplaque levels of calcification biomarkers were affected by treatment with a statin in a cohort of patients with severe carotid stenosis and being asymptomatic for ischemic stroke. Patients on statin therapy had reduced serum osteopontin (OPN), RANKL/osteoprotegerin (OPG) ratio, and MMP-9/pro-MMP-9 activity as compared to untreated patients. Statin-treated patients exhibited increased levels of collagen and reduced neutrophil infiltration in downstream portions of carotid plaques as compared to untreated controls. In upstream plaque portions, OPG content was increased in statin-treated patients as compared to controls. Other histological parameters (such as lipid, macrophage, smooth muscle cell, and MMP-9 content) as well as RANKL, RANK, and OPG mRNA levels did not differ between the two patient groups. Serum RANKL/OPG ratio positively correlated with serum levels of neutrophilic products, intraplaque neutrophil, and MMP-9 content within downstream portions of carotid plaques. In conclusion, statin treatment was associated with improvement in serum RANKL levels and reduced neutrophil activity both systemically and in atherosclerotic plaques.

Impact of short term endothelin A receptor blockade on plasma markers for remodeling and neutrophil activation in patients with ST elevation acute coronary syndrome

Impact of short term endothelin A receptor blockade on plasma markers for remodeling and neutrophil activation in patients with ST elevation acute coronary syndrome

Functional Activity of Neutrophils in Diabetes Mellitus and Coronary Heart Disease: Role of Myeloperoxidase in the Development of Oxidative Stress

We performed a comparative analysis of functional activity of neutrophils in patients with type 2 diabetes mellitus with and without symptoms of CHD. Enhanced H2O2 production by neutrophils in response to N-formyl-Met-Leu-Phe (fMLP) was found in patients with type 2 diabetes mellitus. In patients with type 2 diabetes mellitus associated with CHD, fMLP-induced release of myeloperoxidase from azurophilic granules of neutrophils was reduced and plasma myeloperoxidase level was elevated. Increased peroxidase activity of myeloperoxidase, reduced plasma catalase activity, and increased levels of TBA-reactive lipid peroxidation products and oxidized glutathione were detected in patients of both groups. Since myeloperoxidase is an important neutrophilic mediator of oxidative stress, its increased activity in the blood can be an additional marker of oxidative stress and cardiovascular risk in patients with diabetes mellitus.

Phagocytic and Oxidative Burst Activity of Neutrophils in Patients With Spinal Cord Injury

ObjectiveTo evaluate phagocytic activity and neutrophil oxidative burst functions in patients with spinal cord injury (SCI) because alterations in neutrophil metabolic activity can be one of the causes of immune mechanism damage contributing to repeated bacterial infections. DesignA controlled and cross-sectional study. SettingDepartments of physical medicine and rehabilitation and immunology. ParticipantsPatients with SCI (N=34) and 28 healthy controls. InterventionsPhagocytosis and oxidative burst in whole-blood neutrophils were assessed by flow cytometry. The percentage of phagocytizing cells after in vitro incubation with Escherichia coli, phagocytic activity (mean intensity of fluorescence [MIF]) and the percentage of neutrophiloxidative burst, and the MIF value of the production of reactive oxygen intermediates (ROIs) were analyzed. In addition, clinical assessment including the level of injury, American Spinal Injury Association scores, and functional status were carried out. Main Outcome MeasuresNot applicable. ResultsAlthough the percentage of E. coli phagocytizing neutrophils was not different between groups, the MIF value of absorbed E. coli was significantly lower in patients with SCI than in controls (P<.05). The MIF value of ROI production by neutrophils with both stimulator of phorbol 12-myristate 13-acetate and E. coli was significantly higher in patients with SCI (P<.05). ConclusionsIn patients with SCI, decreased phagocytic activity of neutrophils may be a result of a regulatory mechanism to minimize the deleterious effects of increased neutrophil burst activity.

Neutrophils in acute lung injury

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is characterised by lung oedema due to increased permeability of the alveolar-capillary barrier and subsequent impairment of arterial oxygenation. Lung oedema and endothelial and epithelial injury are accompanied by an influx of neutrophils into the interstitium and alveolar space. Hence, the activation and recruitment of polymorphonuclear neutrophils (PMNs) are thought to play key roles in the progression of ALI/ARDS. Neutrophils, which have anti-microbial activity, are the first cells to be recruited to the site of inflammation. This review focuses on the mechanisms of neutrophil activity in patients with ALIs with respect to attachment, recruitment, adhesion, migration, activation, release of damage mediators, and apoptosis via PMNs.

The Effect of Conventional and Mini-Invasive Cardiopulmonary Bypass on Neutrophil Activation in Patients Undergoing Coronary Artery Bypass Grafting

Interleukin-10 (IL-10) is considered to be a cytokine with potent anti-inflammatory properties, which have been previously linked to increased incidence of sepsis. The level of IL-10 is elevated by cardiac surgery when cardiopulmonary bypass (CPB) and methylprednisolone are used. In our study, we compare the level of IL-10, IL-10 Receptor (IL-10R), and percentage of neutrophils between two groups of cardiac surgical patients undergoing Coronary Artery Bypass Grafting, both of which were not given methylprednisolone. The first group was operated with conventional CPB, while the second group was operated with minimally invasive CPB (mini-CPB). We detected enhanced level of IL-10 during surgery and at the end of surgery in both groups of patients. While no correlation between IL-10 and IL10R was found, IL-10 was positively correlated with increased percentage of neutrophils at the time points when the level of IL-10 peaked.

Changes in cysteinyl leukotrienes during and after cardiac surgery with cardiopulmonary bypass in patients with and without chronic obstructive pulmonary disease

Pulmonary function frequently deteriorates after cardiopulmonary bypass (CPB). Chronic obstructive pulmonary disease (COPD) increases risk of respiratory complications after CPB. Cysteinyl leukotrienes are important mediators of respiratory dysfunction. Their role during cardiac surgery and its lung complications is incompletely understood. We studied whether production of cysteinyl leukotrienes changes during and after cardiac surgery with CPB and differs between patients with and without COPD. Patients with (n=9) and without (n=10) moderate-to-severe COPD undergoing cardiac surgery with CPB were prospectively included. Plasma and urinary cysteinyl leukotriene and leukotriene B(4) concentrations were measured by enzyme-linked immunosorbent assay after anesthesia induction, at end of CPB, after CPB, and 2 hours after intensive care unit admission. Gas exchange and respiratory mechanics were also assessed. Patients with COPD had larger airway resistances after CPB and chest closure (P<.001), lower ratio of arterial Po(2) to inspired oxygen fraction at intensive care unit admission (215 ± 37 vs 328 ± 30 mm Hg, P<.05), and longer postoperative mechanical ventilation (13.7 ± 5.8 vs 6.8 ± 3.4 hours, P<.01). Urinary cysteinyl leukotriene concentrations increased with time in both groups (P<.01), but more in patients with than without COPD (P<.05). Plasma cysteinyl leukotriene concentrations increased significantly between baseline and intensive care unit admission in patients with but not without COPD (P<.01). Concentrations of leukotriene B(4) in plasma and urine did not increase significantly with time and were not different between groups. Release of cysteinyl leukotrienes increases during cardiac surgery with CPB and is larger in patients with than without COPD. This may be related to higher lung and airway production of cysteinyl leukotrienes and neutrophil activation in patients with COPD.

Functional antagonism by GM-CSF on TNF-α-induced CD83 expression in human neutrophils

TNFα-induced expression of CD83 in leukocytes is mediated by NF-κb. The aim of our present study was to investigate the underlying mechanism of a unique functional antagonism between GM-CSF and TNFα-induced up-regulation of CD83 in human neutrophils. CD83 was down-regulated by co-stimulation of neutrophils with TNFα and GM-CSF compared to TNFα alone both at the level of mRNA and protein. In marked contrast, the expression of IL-1RA was up-regulated under the same conditions. The down-regulation of CD83 was not mediated by modulation of the NF-κb signaling pathway. Neither was it mediated by a decrease in mRNA stability of CD83. NF-κb was modulated under these conditions as both the expression of the target gene IL-1RA as well as the phosphorylation of IkBα were up-regulated. Our results show that co-stimulation with pro-inflammatory cytokines such as TNFα and GM-CSF can have differential effects on inflammatory pathways initiated in the same target cell. GM-CSF can both synergize with TNFα in the case of expression of IL1-RA and antagonize in the case of CD83. Therefore, expression of CD83 as read out for activation of neutrophils in patients with inflammatory diseases is complicated by the presence of cross-modulating cytokines such as GM-CSF.

Advanced Oxidation Protein Products

The etiology and pathogenesis of chronic inflammatory bowel diseases are still poorly understood. Oxidative stress takes place in the pathogenesis of ulcerative colitis (UC) and advanced oxidation protein products (AOPP) are accepted as a novel marker of oxidative stress. There are no data concerning whether AOPP may be used as a simple serum marker to assess the disease activity, predict severity of the disease course in UC. In this study, we determine the importance of neutrophil activation and the role of oxidative stress in the pathogenesis of UC, by quantification of AOPP and total thiol levels as markers of oxidative protein damage, malondialdehyde levels as a marker of lipid peroxidation, and myeloperoxidase activity as a marker of neutrophil activation in patients with UC. Serum levels of AOPP, thiol, myeloperoxidase activity, and malondialdehyde were found as increased in UC group compared with controls (P=0.004, 0.047, 0.001, and 0.001 respectively). Our finding of increased levels of plasma AOPP levels supports the presence of oxidative stress and protein oxidation in UC and this marker may be used as a simple serum marker to assess disease activity, predict the severity of disease course, and perhaps response to therapy.

Neutrophil Activation in Patients with ASA-Induced Urticaria

The pathogenic mechanism of acetyl salicylic acid (ASA)-induced urticaria (AIU) is not fully understood. We compared the levels of neutrophil activation and related cytokines in patients with ASA-intolerant acute urticaria (AIAU) and ASA-intolerant chronic urticaria (AICU). A total of 51 patients with AIAU, 88 patients with AICU, and 102 normal controls (NC) were enrolled in this study. The serum levels of myeloperoxidase (MPO), interleukin-8 (IL-8), and IL-18 were compared among the three groups. The serum levels of MPO were highest in the AIAU group, followed by the AICU and NC groups, and the serum levels of IL-18 were significantly higher in the AIAU and AICU groups than in NC group. Within the AIU groups, significant correlations were noted between the levels of MPO and IL-8, and IL-8 and IL-18. In conclusion, neutrophil activation, which was associated with the levels of IL-8 and IL-18 in the AIAU group, may be involved in the pathogenic mechanism of AIU. A role for IL-18 in the pathogenesis of AIU is also suggested.

Platelet vWF, ADAMTS-13, and Neutrophil Activation in Patients with Essential Thrombocythemia (ET)

ET is a chronic myeloproliferative disorder, the benign clinical course of which can be complicated by both thromboses and hemorrhages. The levels of the largest multimers of plasma vWF, are relevant for the hemostatic balance in this disease. vWF is stored in the cellular granules of both endothelial cells and platelets, from which is released upon activation. Neutrophils and platelets circulate in an activation status in ET patients, leading to an increased formation of platelet/neutrophil aggregates. In this study we evaluated in ET patients, the platelet vWF content and its relation to neutrophil activation. In addition, the activity of ADAMTS13, the enzyme responsible for maintaining the normal size distribution of vWF multimers, was studied. A group of 61 consecutive ET patients (50% carrying the JAK2 V617F mutation) and 30 healthy controls were included into the study. Total vWF antigen (vWF:Ag) and activity (vWF:Act) levels were determined in both plasma and in isolated washed platelets by ELISA and collagen binding assay (CBA), respectively. ADAMTS13 activity was measured in plasma according to Gerritsen's method. CD11b and leukocyte alkaline phosphatase (LAP) were measured on neutrophil membrane as activation markers. Plasma vWF:Ag levels resulted significantly increased in ET patients compared to controls (p<0.05), the subgroup of patients with the JAK2 mutation showing the highest levels; whereas vWF:Act was not statistically different. The vWF Act/Ag ratio was significantly lower in ET compared to controls (0.85±0.15 vs 0.95±0.23; p<0.01). A significant inverse relation between platelet count and plasma vWF:Act existed. On the other hand, platelets from these patients had a decreased content of both vWF:Ag and vWF:Act than platelets form controls (p<0.01), suggesting an increased platelet release of vWF. In addition, platelets from ET JAK2 mutation carriers had significantly lower vWF:Act compared to wild-type subjects. Accordingly, the platelet vWF Act/Ag ratio of JAK2 mutation carriers was significantly (p<0.01) lower vs wild-type patients and controls. Neutrophil confirmed to be activated in these patients, as previously described. Indeed, surface activation markers were increased in ET patients compared to controls, and, in particular, CD11b levels were inversely related to platelet vWF:Act (p<0.01). The measurement of plasma ADAMTS13 showed a reduction in the activity of this protease in ET patients (68±16%) compared to normal control mean (p<0.01). In conclusion, in ET patients and particularly in JAK2 mutation carriers, a decrease in platelet vWF:Ag and Act is found and correlates with neutrophil activation, suggesting a role of neutrophil in platelet degranulation. Increased vWF release and reduced ADAMTS13 activity can represent a mechanism of hypercoagulation in these patients.

Isolated Head Injury in Children Affects the Neutrophil Function and Lymphocyte Count

Outcomes of treatment of postinjury complications remain unsatisfactory and research continues into the impact of trauma on innate and acquired immunity. The aim of our study was to describe how head injury affects a child's immunity by measuring the neutrophil function and lymphocytes subsets. The peripheral blood of 16 children with head trauma (Glasgow Coma Score < or =9) was examined. The blood samples were collected on the first and on the seventh day after trauma. The production of reactive oxygen species (ROS), spontaneous and stimulated, the expression of CD11b, and the lymphocyte subpopulations were measured. The blood of healthy children was studied as control. The impact of endotracheal intubation on the examined parameters was analyzed as well. Head trauma leads to the increase of leukocytosis; the total production of ROS by peripheral blood neutrophils does not change after head injury. Correction of the results according to the number of neutrophils revealed a significant decrease in ROS production by a single neutrophil. The expression of adhesion molecule CD11b did not change. Head injury in children causes the decrease of the total lymphocyte count, CD3, CD4, CD8, and natural killer cells count on both the first and the seventh postinjury day. On the seventh day the significant decrease of natural killer cells subset was observed. The CD4/CD8 ratio increased from 1.5 (the first day) to 2.5 (the seventh day). The intubation did not affect the examined parameters. After head injury, total ROS production and adhesion molecule CD11b expression remained unchanged when compared with control. The study did not demonstrate evidence for neutrophil activation in patients with head injuries. The total lymphocyte count was found to be decreased and the composition of lymphocytes' subsets was deeply impaired.

Pretreatment with aminophylline reduces release of Troponin I and neutrophil activation in the myocardium of patients undergoing cardioplegic arrest

Cardioplegic arrest and subsequent reperfusion results in myocardial injury partly related to local inflammation in the heart. It has been proven that aminophylline has numerous anti-inflammatory effects. This study has been designed to evaluate the effects of aminophylline used as a cardioprotective agent for patients undergoing cardiopulmonary bypass (CPB) for valve replacement. Thirty patients undergoing elective valve replacement were randomized to receive either aminophylline (n=15), or normal saline (control n=15). Administration of aminophylline (5mg/kg) was injected intravenously after induction of anesthesia. The cardiac Troponin I (cTnI), myocardial myeloperoxidase (MPO) activity, atrial cyclic AMP, and a coronary sinus neutrophil count were measured before and after cardioplegic arrest. There were no differences between the two groups with regard to clinical variables. The cTnI concentration increased significantly after aortic declamping in both groups. However, it was significantly lower, 8h after aortic declamping, in aminophylline group (1.00+/-0.41 vs 2.37+/-1.35 ng/ml p=0.038). The atrial cAMP was significantly higher before aortic cross-clamping in aminophylline group (42.5+/-6.7 pmol/g tissue vs 30.6+/-12.4 pmol/g tissue p=0.04). In addition, we found that the aminophylline group had a significantly lower MPO after reperfusion (1.50+/-0.58 U/g tissue vs 0.86+/-0.24 U/g tissue p=0.003), and a significantly lower neutrophil count 30 min after aortic declamping (0.68+/-0.11x10(3) cell/ml vs 0.32+/-0.16x10(3) cell/ml, p=0.023). Pretreatment with intravenous aminophylline reduces the subclinical myocardial injury and neutrophil activation in patients undergoing CPB for valve replacement.

Endothelial Microparticles and Their Binding to Leukocytes in Patients with End-Stage Renal Disease.

Background: End-stage renal disease (ESRD) has been associated with endothelial dysfunction, a proinflammatory state and markedly increased cardiovascular risk. Endothelial microparticles (EMP) are released by activated or apoptotic endothelial cells. In vitro studies have shown that EMP can bind and activate neutrophils, suggesting that they may represent not only markers of endothelial status but also mediators of inflammation. The objectives of this study were to:Assess the levels of free EMP and leukocyte-bound EMP in ESRD;Determine whether EMP binding to neutrophils predicts the degree of neutrophil activation in patients with ESRD.Methods: We measured the levels of endothelial microparticles (EMP) and EMP-leukocyte conjugates in 80 patients with ESRD and 35 normal controls. We performed flow cytometry in peripheral venous blood before hemodialysis to measure (1) EMP positive for CD31 (EMP31), E-selectin (EMP62E), CD54 (EMP54); (2) EMP54- and EMP62E-leukocyte conjugates; (3) Neutrophil activation, assessed by expression of activation marker CD11b.Results: Assessment of free EMP revealed that patients with ESRD had slightly elevated levels of free EMP54 but not of free EMP62E or EMP31. However, levels of EMP54-Lymphocyte, EMP54-Monocyte, EMP54-Neutrophil, EMP62E-Lymphocyte and EMP62E-Monocyte conjugates were clearly elevated in patients with ESRD. CD11b expression in leukocytes strongly correlated with levels of EMP54-Neutrophil conjugates (R=0.67; p<0.0001) and EMP62E-Neutrophil conjugates (R=0.66; p<0.0001). Furthermore, both types of conjugates independently predicted CD11b expression (adjusted p<0.05).Conclusions: ESRD is associated with increased binding of EMP to leukocytes, resulting in normal levels of some species of free EMP. Therefore, measurement of both free EMP and EMP-leukocyte conjugates is necessary for adequately assessing EMP release in ESRD. Levels of EMP bound to neutrophils strongly predict neutrophil activation, suggesting that EMP induce neutrophil activation in vivo, consistent with in vitro studies. EMP may represent important mediators of the proinflammatory state in ESRD.EMP and EMP-Leukocyte Conjugates in ESRD patients compared to normal controlsESRD (n=80)Controls (n=35)P valueEMP31 (IQR)842 (484–1546)807 (566–1240)0.97EMP62E (IQR)69 (39–128)60 (43–113)0.96EMP54 (IQR)75 (33–144)34 (18–141)0.04EMP54-Lymphocyte Conjugates (±SD)1.45±0.21.21±0.1<0.0001EMP54-Monocyte Conjugates (±SD)1.77±0.61.27±0.3<0.0001EMP54-Neutrophil Conjugates (±SD)2.12±0.61.85±0.60.02EMP62E-Lymphocyte Conjugates (±SD)1.30±0.21.13±0.1<0.0001EMP62E-Monocyte Conjugates (±SD)1.61±0.51.40±0.30.01EMP62E-Neutrophil Conjugates (±SD)2.04±0.62.05±0.50.95IQR=Interquartile range

Coronary plaque injury triggers neutrophil activation in patients with coronary artery disease

Activation of leukocytes, in particular polymorphonuclear neutrophils (PMN), is considered an early event in unstable coronary disease. Upon activation PMN liberate myeloperoxidase (MPO), an enzyme which binds to the vessel wall and depletes vascular NO bioavailability. Using coronary balloon angioplasty as a trigger to provoke coronary plaque injury, we assessed the time course of neutrophil activation, local and peripheral levels of myeloperoxidase, and systemic vascular NO bioavailability in patients with stable coronary artery disease. Twenty-four patients with stable CAD were enrolled prior to undergoing percutaneous interventions (PCI, n=14) and diagnostic coronary angiography ( n=10), respectively. Following angioplasty arterial MPO plasma levels increased (231.5±67.6 to 273.8±80.4 pg/mg protein; P<0.01) whereas MPO levels in the coronary sinus decreased (240.8 ± 74.4 vs 205.4 ± 60.1 pg/mg protein; P<0.01) in the absence of elevated serum markers for myocardial necrosis. Following PCI, patients revealed impaired vascular NO bioavailability as reflected by reduced brachial flow-mediated dilation (FMD; 6.25±3.03 to 4.90±2.70%; P<0.01), whereas FMD increased in the angiography group. Coronary plaque injury provokes rapid activation of PMN in the absence of myocardial necrosis; the coronary circulation emerges as a primary site for deposition of MPO following injury of the coronary vessel wall. Activation of PMN with release of MPO is not only restricted to the target site, but can be assessed systemically and may represent a critical mechanistic link for impaired systemic vascular NO bioavailability in patients suffering unstable coronary disease.

Intravascular Neutrophil Activation Due to Carbon Monoxide Poisoning

We hypothesized that platelet-neutrophil interactions occur as a result of acute carbon monoxide (CO) poisoning, and subsequent neutrophil activation triggers events that cause neurologic sequelae. To identify platelet-neutrophil interactions and neutrophil activation in patients and in animal models, and to establish the association between these intravascular events and changes linked to CO-mediated neurologic sequelae in an animal model. Blood was obtained from 50 consecutive patients. Abnormalities were variable depending on the carboxyhemoglobin level at study admission and duration of CO exposure. Platelet-neutrophil aggregates were detected and plasma myeloperoxidase (MPO) concentration was significantly elevated in those with confirmed CO poisoning. Among patients exposed to CO for over 3 h, flow cytometry scans of neutrophils revealed increased surface expression of CD18 and, in some groups, MPO on the cell surface. Animal models revealed consistent evidence of platelet-neutrophil aggregates, neutrophil activation and surface MPO, and plasma MPO elevation. MPO was deposited along the brain vascular lining and colocalized with nitrotyrosine. CO poisoning caused abnormalities in the charge pattern of myelin basic protein (MBP), changes linked to adaptive immunologic responses responsible for neurologic sequelae in this model. Changes did not occur in thrombocytopenic rats, those receiving tirofiban to inhibit platelet-neutrophil interactions, or those receiving L-nitroarginine methyl ester to inhibit nitric oxide synthesis. Alterations in MBP did not occur in CO-poisoned knockout mice lacking MPO. Acute CO poisoning causes intravascular neutrophil activation due to interactions with platelets. MPO liberated by neutrophils mediates perivascular oxidative stress, which is linked to immune-mediated neurologic sequelae.

Perceived stress, psychological well‐being and the activity of neutrophils in patients undergoing cardiopulmonary bypass surgery

AbstractThis study explored relationships, before and after surgery, between perceived stress and the activity of white‐blood cells (neutrophils) in 82 patients undergoing heart surgery involving cardiopulmonary bypass surgery (CPB).On the evening before surgery and at follow‐up, 6‐weeks after discharge, patients completed self‐administered standard psychological measures. Small peripheral blood samples were taken, from which neutrophil activity was quantified using nitro‐blue tetrazolium (NBT) and luminol‐dependant chemiluminescence (phagocytic capacity).There were consistent, statistically significant associations between stress and percentageNBT cells at baseline and at follow‐up. Regression analysis showed that perceived stress was a predictor of neutrophil activity at follow‐up suggesting that higher levels of stress are associated with higher levels of activity. Results from the phagocytic capacity data support and strengthen the NBT findings; in response to stimuli the phagocytic capacity of the neutrophils is reduced at baseline (high stress) and increased at follow‐up (lower stress). Significant decreases were found on perceived stress, anxiety, depression, negative affect and health‐related stress at follow‐up. Patients' self‐efficacy was high at baseline and remained high throughout the study.Results highlighted a consistent, significant relationship between perceived stress and the ‘activity’ of neutrophils. The implications of this finding are worthy of exploration given that stress‐activated neutrophils may adversely influence health outcomes. Copyright © 2006 John Wiley &amp; Sons, Ltd.

Investigation of protein oxidation and lipid peroxidation in patients with rheumatoid arthritis

We aimed to determine the importance of neutrophil activation and the source of oxidative stress in the pathogenesis of rheumatoid arthritis (RA) by quantification of advanced oxidation protein products (AOPP) and total thiol levels as markers of oxidative protein damage, malondialdehyde (MDA) levels as a marker of lipid peroxidation and myeloperoxidase (MPO) activity as a marker of neutrophil activation in patients with RA. Fifty-seven rheumatoid arthritis patients were included in the study and sub-grouped according to disease activity (active, n = 31; inactive, n = 26) and compared with healthy controls (n = 25). Serum MPO activity, AOPP, MDA, and thiol levels were measured by an enzymic spectrophotometric method. Serum MPO activity (p < 0.001), AOPP (p < 0.001), MDA (p < 0.001) and levels of thiol (p < 0.002), were higher in the patient group than the controls. Active and inactive RA groups were compared with the control group and there were significant differences between each parameter. MPO activity, AOPP, MDA and thiol levels were significantly higher in both active and inactive RA patients than the controls. On the other hand, when a comparison was made between active and the inactive stage, a statistically significant difference was present only in MDA (p < 0.05) and AOPP levels (p < 0.05). There was also a significant positive correlation between all parameters. These data strongly suggest that neutrophils, which constitute the most important source of chlorinated oxidants due to their high MPO content, may be involved in serum AOPP formation and therefore the production of a novel class of pro-inflammatory mediators of oxidative stress in RA patients and that protein oxidation could play an important role in the pathogenesis of RA as does lipid peroxidation.

Automated quantitation of peripheral blood neutrophil activation in patients with myocardial ischaemia

Background: Coronary ischaemic syndromes are associated with neutrophil activation. The Bayer automated haematology analysers can detect increased light scatter of neutrophil populations, which correlates with neutrophil activation. We aimed to assess the role of an automated analyser in detecting systemic neutrophil activation in peripheral blood samples of patients with coronary ischaemia. Methods: A prospective cross-sectional study was undertaken in 18 patients with chronic stable angina, 9 with unstable angina and 26 normal control subjects. Whole blood samples were taken to assess neutrophil count and light scatter, and serum samples were taken from some patients for assessment of Troponin T, C-reactive protein (CRP) and myeloperoxidase (MPO). In addition, whole blood was stimulated in vitro with interleukin (IL)-8 and N-formyl-methionyl-leucyl-phenylalanine (fMLP) to assess changes in neutrophil light scatter detected by the analyser. Results: Neutrophil light scatter was increased in patients with chronic stable and unstable angina compared to normal control subjects (normal subjects 74.1 (73.3, 75.0) (mean arbitrary units (95% confidence intervals, (CI)) vs. 78.6 (76.9, 80.3) in the chronic stable angina group P<0.001 and 77.1 (75.3, 79.0) in the unstable angina group P<0.007). In vitro stimulation of whole blood produced comparable increases in neutrophil light scatter when morphological changes in neutrophils were demonstrable under electron microscopy. Conclusions: Automated measurement of neutrophil activation by light scatter is possible using the Advia 120 analyser and is superior to a neutrophil count in discriminating groups with angina. This technique may be useful in monitoring disease activity and progression in coronary artery disease and in guiding the use of anti-inflammatory therapies.

Randomized study comparing the effects of hydroxyethyl starch solution with Gelofusine on pulmonary function in patients undergoing abdominal aortic aneurysm surgery

Restoring blood flow to ischaemic tissue can cause lung damage with pulmonary oedema. Hydroxyethyl starch (HES) solution, when used for volume replacement, may modify and reduce the degree of ischaemia-reperfusion injury. We compared the effects of HES solution with those of Gelofusine solution on pulmonary function, microvascular permeability and neutrophil activation in patients undergoing elective infrarenal abdominal aortic aneurysm surgery. Forty patients were randomized into two groups. The anaesthetic technique was standardized. Lung function was assessed with the PO(2)/FI(O(2)) ratio, respiratory compliance, chest x-ray and a score for lung injury. Microvascular permeability was determined by measuring microalbuminuria. Neutrophil activation was determined by measurement of plasma elastase. Four hours after surgery, the median (quartile values) PO(2)/FI(O(2)) ratio was 40.3 (37.8, 53.1) kPa for the HES-treated patients compared with 33.9 (31.2, 40.9) kPa for the Gelofusine-treated patients (P<0.01, Mann-Whitney test). The respiratory compliance was 80 (73.5, 80) ml cm(-1) H(2)O in the HES-treated patients compared with 60.1 (50.8, 73.3) ml cm(-1) H(2)O in the Gelofusine-treated patients (P<0.01, Mann-Whitney test). The lung injury score 4 h after surgery was less for the patients treated with HES compared with the patients treated with Gelofusine (0.33 vs 0.71, P=0.01, Wilcoxon rank sum test). Mean (SD) plasma elastase was less in the HES-treated patients on the first postoperative day (1.96 (0.17) vs 2.08 (0.24), P<0.05). The log mean microalbuminuria was less in the HES-treated patients (0.41 vs 0.91 mg mmol(-1), P<0.05). This difference in microvascular permeability was associated with different volumes of colloid required to maintain stable cardiovascular measurements in the two groups of patients studied (3000 vs 3500 ml, P<0.01, Mann-Whitney test). Compared with Gelofusine, the perioperative pulmonary function of patients treated with HES after abdominal aortic aneurysm surgery was better.