Resistance Exercise Selectively Mobilizes Monocyte Subsets: Role of Polyphenols.

PURPOSE: To examine the impact of polyphenol supplementation on the recruitment, mobilization, and activation of monocyte subsets after resistance exercise. METHODS: Thirty-eight recreationally active males (22.1 ± 3.1 yr; 173.9 ± 7.9 cm; 77.8 ± 14.5 kg) were assigned to 28 d of polyphenol blend (PPB) supplementation, placebo (PL), or control (CON). Blood samples were obtained before (PRE) postresistance exercise, immediately (IP) postresistance exercise, 1 h (1H) postresistance exercise, 5 h (5H) postresistance exercise, 24 h (24H) postresistance exercise, and 48 h (48H) postresistance exercise (PPB/PL) or rest (CON). Fine-needle biopsies were obtained from the vastus lateralis at PRE, 1H, 5H, and 48H. Circulating concentrations of macrophage chemoattractant protein-1 (MCP-1) and fractalkine, as well as intramuscular MCP-1 were analyzed via multiplex assay. Changes in the proportions and expression of CD11b on monocyte subsets were assessed via flow cytometry. RESULTS: Circulating MCP-1 increased in PPB and PL at IP with further increases at 5H. Intramuscular MCP-1 was increased at 1H, 5H, and 48H in all groups. Classical monocyte proportions were reduced in PPB and PL at IP, and increased at 1H. Nonclassical monocytes were increased in PPB and PL at IP, whereas intermediate monocytes were increased at IP, and reduced at 1H. Intermediate monocytes were increased in PPB at 24H and 48H. CD11b expression was reduced on PPB compared with PL and CON at PRE on intermediate and nonclassical monocytes. CONCLUSIONS: Resistance exercise may elicit selective mobilization of intermediate monocytes at 24H and 48H, which may be mediated by tissue damage. Additionally, polyphenol supplementation may suppress CD11b expression on monocyte subsets at rest.

Monocyte Recruitment after High-Intensity and High-Volume Resistance Exercise.

UNLABELLED: The innate immune response is generally considered to have an important role in tissue remodeling after resistance exercise. PURPOSE: The purpose of this study was to compare changes in markers of monocyte recruitment after an acute bout of high-intensity (HVY) versus high-volume (VOL) lower-body resistance exercise. METHODS: Ten resistance-trained men (24.7 ± 3.4 yr, 90.1 ± 11.3 kg, 176.0 ± 4.9 cm) performed each protocol in a randomized, counterbalanced order. Blood samples were collected at baseline, immediately (IP), 30 min (30P), 1 h (1H), 2 h (2H), and 5 h (5H) postexercise. Plasma concentrations of monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor alpha (TNF-α), myoglobin, and cortisol were measured via assay. Tumor necrosis factor receptor 1 (TNFr1), macrophage-1 antigen (cluster of differentiation 11b [CD11b]), and C-C chemokine receptor 2 (CCR2) expression levels were measured using flow cytometry. TNFr1 and CD11b were assessed on CD14CD16 monocytes, whereas CCR2 was assessed on CD14 monocytes. RESULTS: Plasma myoglobin concentrations were significantly greater after HVY compared with VOL (P < 0.001). Changes in plasma TNF-α, MCP-1, and expression levels of CCR2 and CD11b were similar between HVY and VOL. When collapsed across groups, TNF-α was significantly increased at IP, 30P, 1H, and 2H (P values < 0.05), whereas MCP-1 was significantly elevated at all postexercise time points (P values < 0.05). CCR2 expression on CD14 monocytes was significantly lower at IP, 1H, 2H, and 5H (P values < 0.05). CD11b expression on CD14 CD16 was significantly greater at IP (P < 0.014) and 1H (P = 0.009). TNFr1 expression did not differ from baseline at any time point. Plasma cortisol concentrations did not seem to be related to receptor expression. CONCLUSIONS: Results indicate that both HVY and VOL protocols stimulate a robust proinflammatory response. However, no differences were noted between resistance exercise training paradigms.

Inhibition of Ras signalling reduces neutrophil infiltration and tissue damage in severe acute pancreatitis.

Neutrophil recruitment is known to be a rate-limiting step in mediating tissue injury in severe acute pancreatitis (AP). However, the signalling mechanisms controlling inflammation and organ damage in AP remain elusive. Herein, we examined the role of Ras signalling in AP. Male C57BL/6 mice were treated with a Ras inhibitor (farnesylthiosalicylic acid, FTS) before infusion of taurocholate into the pancreatic duct. Pancreatic and lung tissues as well as blood were collected 24 h after pancreatitis induction. Pretreatment with FTS decreased serum amylase levels by 82% and significantly attenuated acinar cell necrosis, tissue haemorrhage and oedema formation in taurocholate-induced pancreatitis. Inhibition of Ras signalling reduced myeloperoxidase (MPO) levels in the inflamed pancreas by 42%. In addition, administration of FTS decreased pancreatic levels of CXC chemokines as well as circulating levels of interleukin-6 and high-mobility group box 1 in animals exposed to taurocholate. Moreover, treatment with FTS reduced taurocholate-induced MPO levels in the lung. Inhibition of Ras signalling had no effect on neutrophil expression of Mac-1 in mice with pancreatitis. Moreover, FTS had no direct impact on trypsin activation in isolated pancreatic acinar cells. These results indicate that Ras signalling controls CXC chemokine formation, neutrophil recruitment and tissue injury in severe AP. Thus, our findings highlight a new signalling mechanism regulating neutrophil recruitment in the pancreas and suggest that inhibition of Ras signalling might be a useful strategy to attenuate local and systemic inflammation in severe AP.

Platelet glycoprotein Ib-IX as a regulator of systemic inflammation.

OBJECTIVE: The platelet glycoprotein Ib-IX (GP Ib-IX) receptor is a well-characterized adhesion receptor supporting hemostasis and thrombosis via interactions with von Willebrand factor. We examine the GP Ib-IX/von Willebrand factor axis in murine polymicrobial sepsis, as modeled by cecal ligation and puncture (CLP). APPROACH AND RESULTS: Genetic absence of the GP Ib-IX ligand, von Willebrand factor, prolongs survival after CLP, but absence of the receptor, GP Ib-IX, does not. Because absence of either von Willebrand factor or GP Ib-IX significantly impairs hemostasis and thrombosis, we sought to define additional GP Ib-IX-dependent pathways impacting survival in the CLP model. We document that the absence of GP Ib-IX leads to reduced platelet-neutrophil and platelet-monocyte interactions. Twenty-four hours after CLP, absence of GP Ib-IX coincides with an alteration in cytokine levels, such as tumor necrosis factor-α secreted by monocytes, and increased macrophage-1 antigen expression by neutrophils. CONCLUSIONS: In contrast to the well-characterized proinflammatory properties of platelets, we describe in the CLP model an anti-inflammatory property associated with platelet GP Ib-IX. Thus, a single platelet receptor displays a dual modulatory role in both the thrombotic and inflammatory pathways associated with polymicrobial sepsis. In sharing leucine-rich motifs with toll-like receptors, platelet GP Ib-IX can be considered a multifunctional participant in hemostasis, thrombosis, and the inflammatory cascade. The results highlight a dynamic role for platelets in systemic inflammation and add to the complex pathophysiologic events that occur during the dysregulated coagulation and inflammation associated with sepsis.

Prasugrel inhibits platelet-leukocyte interaction and reduces inflammatory markers in a model of endotoxic shock in the mouse.

Prasugrel, through its active metabolite, reduces atherothrombosis and its clinical manifestations by inhibiting platelet activation and aggregation. Platelets also contribute to inflammation through interaction with different classes of leukocytes. We investigated whether the inhibitory effect of prasugrel on platelets also counteract inflammatory responses. The effect of prasugrel active metabolite, R-138727, was investigated on platelet P-selectin expression, platelet adhesion to polymorphonuclear leukocytes (PMN) and monocytes (MN) and Mac-1 expression in PMN and MN, in vitro, in human cells. The ex vivo effect of prasugrel administration on P-selectin, thromboxane (TXB)2 formation, platelet-PMN conjugates and Mac-1 expression in PMN triggered by PAR-4 agonist peptide was examined in whole blood from healthy mice as well as from mice in which an acute inflammatory reaction was induced by treatment with endotoxin. The effect of prasugrel on inflammatory markers in endotoxin-treated animals was also tested in vivo. R-138727 inhibited agonist-stimulated expression of platelet P-selectin, platelet-PMN and platelet-MN adhesion and platelet-dependent Mac-1 expression in leukocytes. Addition of aspirin did not modify the inhibitory effect elicited by R-138727. Treatment of mice with prasugrel resulted in a profound inhibition of platelet P-selectin expression, TXB2 production, platelet-PMN adhesion and Mac-1 expression in PMN induced by ex vivo stimulation with PAR-4 agonist peptide of whole blood from healthy or endotoxin-treated mice. Measurement of markers revealed that prasugrel reduced TXB2 and tumour necrosis factor-α synthesis and increased nitric oxide metabolites in endotoxin-treated mice in vivo. In conclusion, prasugrel reduces platelet interactions with PMN and MN. Through these effects prasugrel may curb platelet-mediated inflammatory responses.

Aggressive and chronic periodontitis correlate with distinct cellular sources of key immunoregulatory cytokines.

BACKGROUND: Chronic periodontitis (CP) and aggressive periodontitis (AP) are inflammatory diseases and the main cause of dental loss in adults. We aimed to investigate the expression of adhesion molecules and the source of proinflammatory and anti-inflammatory cytokines in circulating mononuclear cells from patients with CP and AP. METHODS: Peripheral blood mononuclear cells from healthy controls and CP or AP patients were collected. The expression of the cell adhesion molecules CD11a and CD11b, and the cellular sources of interleukin (IL)-4, IL-10, IL-12, interferon-γ, and tumor necrosis factor-α by distinct subpopulations of circulating leukocytes were determined using flow cytometry. RESULTS: The expression of CD11a, but not CD11b, was significantly higher within the CD4(+) and CD8(+) T cells in CP and AP than in healthy controls. The frequencies of tumor necrosis factor-α-expressing CD4(+) T cells and CD14(+) cells were higher in AP and CP, compared to healthy controls, respectively. Moreover, the frequency of IL-10 expressing CD14(+) cells was higher in CP, but not AP, compared to healthy controls CD4(+) T cells committed to IL-4 production was higher in CP than in healthy controls. CONCLUSION: These results suggest the participation of CD11a in the pathogenesis of periodontal lesions and show distinct cellular sources of immunoregulatory cytokines in AP versus CP.

Airway inflammation and upregulation of beta2 Mac-1 integrin expression on circulating leukocytes of female ragpickers in India.

OBJECTIVES: Over one million ragpickers collect and sale recyclable materials from municipal solid wastes (MSW) in India for a living. Since MSW contains a host of pathogenic microorganisms, we investigated the occurrence of airway inflammation and its underlying mechanism in 52 non-smoking female ragpickers (median age 29 yr) and 42 control women matched for age, smoking habit and socioeconomic conditions in Kolkata, eastern India. METHODS: Spontaneously expectorated sputum were stained using the Papanicolau method for cytology, and flow cytometry was used for measurements of surface expression of beta(2) Mac-1 integrin (CD11b/CD18) on leukocytes and P-selectin on platelets. The concentrations of pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) and chemokine interleukin-8 (IL-8) were measured in plasma by enzyme-linked immunosorbent assay. RESULTS: Compared with controls, sputum samples of ragpickers contained significantly increased numbers of alveolar macrophages, neutrophils, eosinophils and lymphocytes, suggesting airway inflammation. Circulating neutrophils and monocytes of the ragpickers overexpressed CD11b/CD18 and their platelets had upregulated surface expression of P-selectin, implying functional activation of these cells. In addition, plasma levels of IL-8 and TNF-alpha were significantly increased, indicating greater trafficking of leukocytes from circulation to the tissues. Multivariate logistic regression analysis demonstrated a positive association between the ragpicking profession and leukocyte activation after controlling for potential confounders. CONCLUSIONS: Ragpickers experience leukocyte and platelet activation and airway inflammation that could make them more vulnerable to tissue damage and cardiovascular diseases.

Glutamine reduces the expression of leukocyte integrins leukocyte function-associated antigen-1 and macrophage antigen-1 in mice exposed to arsenic.

Chronic arsenic exposure results in an increased oxidative stress and inflammation in the body. Glutamine (GLN) is an amino acid considered to have immunomodulatory effects and attenuate the inflammatory reaction. This study was designed to examine the effect of GLN supplementation on inflammatory-related leukocyte integrin expression and in vitro splenocyte cytokine production in mice exposed to arsenic. Mice were assigned to the control and experimental groups. The control group drank deionized water, whereas the experimental group drank deionized water containing 50 ppm of sodium arsenite. Each control and experimental group was further divided into 2 subgroups and fed diets for 5 weeks. One subgroup was fed a semipurified diet, whereas the other subgroup was fed a diet where part of the casein was replaced with GLN, which provided 25% of the total amino acid nitrogen. The results showed that plasma GLN levels of mice in the arsenic group were significantly lower than those in the control groups. Glutamine supplementation reversed the depletion of plasma GLN in the arsenic group. beta(2) intergins, including leukocyte function-associated antigen-1 and macrophage antigen-1 expressed by leukocytes, were significantly higher in the arsenic group than the control groups. Glutamine supplementation reduced leukocyte integrin expression in mice exposed to arsenic. There were no differences in interleukin 4, interleukin 6, interferon gamma, and tumor necrosis factor alpha production between the 2 arsenic groups when splenocytes were stimulated with mitogen. These results suggest that arsenic exposure results in depletion of plasma GLN and higher leukocyte integrin expression. Glutamine supplementation normalized the plasma GLN levels and reduced leukocyte leukocyte function-associated antigen-1 and macrophage antigen-1 expression. However, cytokine modulation may not be responsible for reducing leukocyte integrin expression in mice exposed to arsenic.

Inhaled nitric oxide attenuates reperfusion inflammatory responses in humans.

BACKGROUND: Reduced bioavailability of endothelium-derived nitric oxide associated with reperfusion could potentially exacerbate the inflammatory response during reperfusion. Evidence suggests the pharmacologic effects of inhaled nitric oxide may extend beyond the pulmonary vasculature, and this is attributed to nitric oxide-derived complexes in blood that ultimately orchestrate antiinflammatory effects. In this study, the authors evaluated the potential for inhaled nitric oxide (80 ppm) to attenuate inflammation instigated by ischemia-reperfusion in a human model using patients undergoing knee surgery where a tourniquet was used to produce a bloodless surgical field. METHODS: Inhaled nitric oxide (80 ppm) was administered before tourniquet application and continued throughout reperfusion until the completion of surgery. Venous blood samples were collected before and after reperfusion, for the measurements of nitrate and nitrite, CD11b/CD18, soluble P-selectin, and lipid hydroperoxide. Muscle biopsies were obtained from the quadriceps muscle before skin closure and analyzed for myeloperoxide, conjugated dienes, and nuclear factor-kappaB translocation. RESULTS: Administration of inhaled nitric oxide (80 ppm) significantly attenuated the inflammatory response characterized by reduced expression of CD11b/CD18, P-selectin, and nuclear factor kappaB compared with the control group. This was accompanied by increased plasma levels of nitrate and nitrite and reduced oxidative stress. CONCLUSIONS: Administration of inhaled nitric oxide at 80 ppm significantly reduces inflammation in lower extremity ischemia-reperfusion in humans. This observation supports the concept that during diseases characterized by dysfunction in nitric oxide metabolism, inhaled nitric oxide may be an effective therapy to replenish systemic nitric oxide, thus retarding inflammatory-mediated injury.

Granulocyte and monocyte adsorption apheresis (GCAP) for refractory skin diseases caused by activated neutrophils and psoriatic arthritis: evidence that GCAP removes Mac-1-expressing neutrophils.

In the present study, we have shown that granulocyte and monocyte adsorption apheresis (GCAP), an extracorporeal apheresis instrument whose column contains cellulose acetate (CA) beads, is useful for skin diseases attributable to activated granulocytes and psoriatic arthritis (PsA). We assessed the clinical effectiveness of GCAP and investigated the mechanisms underlying the adsorption of pathogenic granulocytes. The effect of GCAP was assessed in 14 patients with neutrophilic dermatoses and 16 with PsA. The mechanisms by which the instrument adsorbs activated granulocytes were investigated using an in vitro mini-column system that mimics the GCAP. Skin lesions and arthropathy improved in 22 of 29 patients (75.9%) and 14 of 18 (77.8%), respectively. Mac-1 (CD11b/CD18) expression on the peripheral neutrophils, increased compared with normal subjects, was reduced by GCAP. In the mini-column system, CA beads adsorbed 50% neutrophils; and adsorption was inhibited significantly by treating plasma with EDTA and blood cells with antihuman CD11b monoclonal antibody. GCAP was useful for treating neutrophilic dermatoses and PsA. GCAP adsorbs Mac-1-expressing neutrophils to the CA beads by the binding of complement component (iC3b) on CA beads and CD11b expressed on activated neutrophils.

Expression of MAC-1 (CD11b) in acute myeloid leukemia (AML) is associated with an unfavorable prognosis.

There is evidence to suggest, that cellular adhesion molecules and receptors could play a role in leukemia, e.g., through altered adhesive qualities of leukemic blasts. We have studied the expression of the beta2-integrin Mac-1 (CD11b) on mononuclear cells in 48 patients with AML at first diagnosis by flow cytometry using a direct fluorescein-conjugated antibody. A case was defined as positive if more than 20% of the cells expressed Mac-1. Within the FAB types, we observed a high expression rate in cases with M5 (100% MAC-1+ cases, 73% MAC-1+ cells), M4 (75% MAC-1+ cases, 48% MAC-1+ cells) and in cases with FAB-M1 with 71% MAC-1+ cases and 29% MAC-1+ cells. Separating our patients' cohort in cytogenetic risk groups, we could detect significant higher proportions of MAC-1+, cases (88% vs. 27%, P = 0.005) and cells (51% vs. 16%, P = 0.015) with poor cytogenetic risk compared to the favorable risk group. For clinical evaluations only patients treated according to the protocols of the German AML Cooperative Group (AML-CG) were included (n = 29, cases with AML-M3 were excluded). More MAC-1+ cases and cells were found in the "non-responders" group (n = 8) compared to the "responders" group (n = 24). We can conclude that AML cases with high MAC-1 expression are characterized by a worse prognosis. Evaluation of MAC-1 expression in AML might therefore contribute clinically important data with respect to develop new therapies that influence the interactions between integrins like MAC-1 on leukemic cells and endothelial or immunoreactive cells.

[The effect of interferon-gamma in collagen-induced arthritis in mice shows a mechanism of expanding Mac-1+ blood cells during its pathogenesis]. / Onderzoek naar de werking van interferon-gamma in collageen-geïnduceerde artritis in muizen legt een mechanisme van expanderende Mac-1+ cellen bloot in de pathogenese.

Collagen-induced arthritis (CIA) is an animal model for human rheumatoid arthritis. CIA is induced in the mouse by immunization with collagen type II in complete Freund's adjuvant (CFA). As a result of this immunization, mice will develop an autoimmune disease that is characterized by an inflammatory and destructive affection of the joints. IFN-gammaR KO mice have an increased susceptibility to CIA as compared to wild-type control animals: they developed arthritis with a significant earlier disease onset and a higher disease incidence and score. The results indicate that IFN-gamma acts as a disease-protective factor in CIA. The disease-protective effect of IFN-gamma in CIA appeared to be due to CFA that was used for the induction of CIA, and more precisely to the presence of killed mycobacteria in this adjuvant. The killed mycobacteria in CFA elicited in mice an extramedullar myelopoiesis and an expansion of Mac-1+ cells that was strongly inhibited by endogenous IFN-gamma. Parts of the expanded Mac-1+ splenocytes were precursor cells for osteoclasts, they migrated to the joints after challenge with SDF-1, where they found to differentiate into mature osteoclasts who are responsible for bone destruction. The mechanism of expansion, migration and osteoclast activation occurred in IFN-gammaR KO as well as in wild-type mice, but was much more pronounced in the mutant mice. Thus, the use of IFN-gammaR KO mice has exposed a new mechanism in the pathogenesis of autoimmune arthritis in mice. These findings may have important clinical perspectives.

Activation of neutrophils and monocytes by a leukocyte-depleting filter used throughout cardiopulmonary bypass.

OBJECTIVE: Cardiopulmonary bypass elicits systemic inflammation. Depletion of circulating leukocytes might alleviate inflammatory response. We studied the effects of a leukocyte-depleting filter on phagocyte activation during cardiopulmonary bypass. METHODS: Fifty patients undergoing coronary artery bypass grafting were randomly allocated into an arterial line leukocyte filter group (n = 25) with a Pall LeukoGuard 6 leukocyte-depleting filter (LG6; Pall Biomedical, Portsmouth, United Kingdom) and a control group without any filter (n = 25). Blood sampling took place from arterial line at predetermined time points. In the filter group, the sample was taken immediately before the filter; to evaluate activation at the site, an additional sample was taken immediately after the filter. CD11b/CD18 and L-selectin expressions and basal production of hydrogen peroxide were determined with whole-blood flow cytometry, and plasma lactoferrin level was determined with enzyme-linked immunosorbent assay. RESULTS: Neutrophil CD11b expression was higher in the filter group than in the control group (P < .001). Likewise, monocyte CD11b expression, neutrophil hydrogen peroxide production, and lactoferrin plasma levels were all significantly higher, whereas neutrophil and monocyte counts and neutrophil L-selectin expression were all significantly lower in the filter group (all P < .001). At 5 minutes of CPB, CD11b expression increased across the filter on neutrophils (median difference 197 relative fluorescence units, range 45-431 relative fluorescence units, P < .001) and monocytes (median difference 26 relative fluorescence units, range -68-111 relative fluorescence units, P < .001). CONCLUSION: The LG6 arterial line leukocyte filter is ineffective in its principal task of diminishing phagocyte activation during cardiopulmonary bypass.

Dehydroepiandrosterone protects the microcirculation of muscle flaps from ischemia-reperfusion injury by reducing the expression of adhesion molecules.

Adhesion molecules contribute to ischemia-reperfusion injury by increasing the endothelial adhesion and extravasation of leukocytes. Scientific evidence suggests that presurgical treatment with dehydroepiandrosterone may protect the microvasculature against this damage, but the exact mechanism is not known. The purpose of this study was to investigate the effects of presurgical dehydroepiandrosterone treatment on microcirculatory hemodynamic parameters and the expression of adhesion molecules in a rat cremaster muscle flap model. Twenty male rats were randomly assigned to three experimental groups. In group I (n = 5), the muscle flaps did not receive presurgical treatment. In group II (n = 6), propylene glycol (30 mg/kg), the vehicle for dehydroepiandrosterone, was injected intravenously before ischemia was induced. In group III (n = 9), dehydroepiandrosterone (30 mg/kg) was injected intravenously before ischemia was induced. All flaps were subjected to 6 hours of ischemia and 90 minutes of reperfusion. Microcirculatory variables (functional capillary density, red blood cell velocity in the main flap arteriole, and numbers of rolling, sticking, and transmigrating leukocytes), blood levels of three adhesion molecules (L-selectin, Mac-1 integrin, and CD44), and the numbers of leukocytes expressing those molecules were analyzed. Analysis of the microcirculatory parameters revealed that dehydroepiandrosterone treatment before ischemia had significant preservative effects on the red blood cell velocity and functional capillary density 30 and 90 minutes after reperfusion, compared with the control and vehicle-treated groups. Leukocyte-endothelial cell interactions were also affected by dehydroepiandrosterone treatment, as reflected by significant decreases in the numbers of sticking and transmigrating leukocytes 30 and 90 minutes after reperfusion. In dehydroepiandrosterone-treated animals, leukocytes exhibited lower levels of expression of adhesion molecules after the onset of ischemia, compared with the control groups. In this study, intravenous dehydroepiandrosterone administration reduced the activation of leukocytes and improved red blood cell velocity and capillary perfusion in the muscle flap microcirculation during ischemia-reperfusion injury. This protective effect was most likely the result of delayed expression of Mac-1 integrin, L-selectin, and CD44 molecules on leukocytes.

Comparison of m-RNA expression for inflammatory mediators in leukocytes between on-pump and off-pump coronary artery bypass grafting.

OBJECTIVE: Coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) is associated with a systemic inflammatory response. This is mainly attributed to cytokine release caused by CPB and global myocardial ischemia. Coronary artery bypass grafting without cardiopulmonary bypass (off-pump CABG, OPCAB) is now accepted as a less invasive technique than conventional CABG. This study was designed to compare the inflammatory response at the m-RNA level of proinflammatory cytokines and adhesion molecules before and after operation in patients undergoing CABG with and without CPB. METHODS: Twenty patients who underwent isolated CABG with CPB (on-pump group, n=10) or without CPB (off-pump group, n=10) were studied. By utilizing a semiquantitative reverse transcription polymerase chain reaction (RT-PCR) technique, gene expression of cytokines, adhesion molecules, and vasoactive substances in leukocytes of peripheral blood were evaluated before and six hours after surgery. RESULTS: Postoperative expression of m-RNA for interleukin (IL)-1, -8, and -10, tumor necrosis factor (TNF)-alpha, heme oxygenase (HO)-1, platelet endothelial cellular adhesion molecule (PECAM) and Mac-1 increased significantly in the on-pump group but not in the off-pump group (p<0.05). CONCLUSIONS: In view of the m-RNA level of proinflammatory cytokines and adhesion molecules, it can be concluded that OPCAB is a less invasive technique than on-pump CABG. Direct contact of circulating blood with the synthetic surfaces of the CPB system may be the main cause of the systemic inflammation.

Monocyte and neutrophil adhesion molecule expression during acute hyperglycemia and after antioxidant treatment in type 2 diabetes and control patients.

OBJECTIVE: We hypothesized that acute hyperglycemia (an independent cardiovascular risk factor) increases the expression of proatherogenic leukocyte adhesion molecule in type 2 diabetes and controls and that the expression of these adhesion molecules would be antioxidant sensitive. METHODS AND RESULTS: Twenty-three type 2 diabetes patients and 13 control patients underwent two oral glucose tolerance tests 14 days apart and took placebo or 800 IU daily of oral alpha tocopherol between tests. Monocyte and neutrophil expression of adhesion molecules Mac-1, LFA-1 and 3, ICAM-1, and VLA-4 were measured at 0, 120, and 240 minutes by using laser flow cytometry. Baseline adhesion molecule expression did not differ between groups, but there was a rapid, highly significant increase (P<0.0001) in the intensity of monocyte Mac-1 expression after a glucose load in both groups. Alpha-tocopherol supplementation reduced only Mac-1 expression in the diabetes group (P=0.03). CONCLUSIONS: Acute glycemic excursions of any degree cause highly significant, rapid increases in monocyte Mac-1 expression in type 2 diabetes patients and controls. Mac-1 mediates leukocyte vascular infiltration and is prothrombotic. These data suggest a mechanism for the link between glycemic excursions and increased vascular event rates.

Increased generation of dendritic cells from myeloid progenitors in autoimmune-prone nonobese diabetic mice.

Aberrant dendritic cell (DC) development and function may contribute to autoimmune disease susceptibility. To address this hypothesis at the level of myeloid lineage-derived DC we compared the development of DC from bone marrow progenitors in vitro and DC populations in vivo in autoimmune diabetes-prone nonobese diabetic (NOD) mice, recombinant congenic nonobese diabetes-resistant (NOR) mice, and unrelated BALB/c and C57BL/6 (BL/6) mice. In GM-CSF/IL-4-supplemented bone marrow cultures, DC developed in significantly greater numbers from NOD than from NOR, BALB/c, and BL/6 mice. Likewise, DC developed in greater numbers from sorted (lineage(-)IL-7Ralpha(-)SCA-1(-)c-kit(+)) NOD myeloid progenitors in either GM-CSF/IL-4 or GM-CSF/stem cell factor (SCF)/TNF-alpha. [(3)H]TdR incorporation indicated that the increased generation of NOD DC was due to higher levels of myeloid progenitor proliferation. Generation of DC with the early-acting hematopoietic growth factor, flt3 ligand, revealed that while the increased DC-generative capacity of myeloid-committed progenitors was restricted to NOD cells, early lineage-uncommitted progenitors from both NOD and NOR had increased DC-generative capacity relative to BALB/c and BL/6. Consistent with these findings, NOD and NOR mice had increased numbers of DC in blood and thymus and NOD had an increased proportion of the putative myeloid DC (CD11c(+)CD11b(+)) subset within spleen. These findings demonstrate that diabetes-prone NOD mice exhibit a myeloid lineage-specific increase in DC generative capacity relative to diabetes-resistant recombinant congenic NOR mice. We propose that an imbalance favoring development of DC from myeloid-committed progenitors predisposes to autoimmune disease in NOD mice.

The effect of obesity on neutrophil Fc receptors and adhesion molecules (CD16, CD11b, CD62L).

BACKGROUND: There is a large body of epidemiological data associating obesity with a wide variety of clinical disease processes, including cancer and wound infections. However, defining the specific defects of neutrophils has proved difficult and often contradictory. METHODS: 27 patients having gastric bypass surgery for obesity (BMI > 40) were compared with 10 normal controls (BMI < 26). Relative neutrophil frequencies and expression of the activation antigens CD11b (integrin adhesion molecule), CD16 (Fc receptor), and CD62L (L-selectin), were evaluated by flow cytometry. RESULTS: The study control group had a mean age of 37 +/- 7.6 yrs (range 30 to 57) with no significant health problems. Their mean BMI was 23 +/- 2.5 kg/m2 (range 21-26). The mean age of the sample group was 40.36 +/- 13.7 yrs (range 18 to 60) with a mean BMI of 52 +/- 8.2 kg/m2 (range 41 to 72). These patients had a large spectrum of diseases that afflict the morbidly obese, including hypertension (14), arthritis (10), exertional dyspnea (13), venous stasis (7), hypothyroidism (2), NIDDM (3), heart murmur (1), along with 8 smokers. The neutrophil frequency in the obese patients was comparable to the controls (control 49% vs obese 51%). Additionally, there was no apparent difference between obese and controls regarding CD11b or CD16 expression (424 vs 498 gmf) (267 vs 262 gmf). However, there was a significant reduction of CD62L (L-selectin) expression noted in the morbidly obese with respect to controls (102 vs 303 gmf, p < 0.001). An increased percentage of eosinophils when compared to controls (6.7% vs 1.73%, p < 0.001) was also observed. CONCLUSION: Discordant CD11b/CD62L levels, depressed levels of CD62L, and elevated eosinophil percentages support the hypothesis that a chronic inflammatory state exists in morbid obesity. Decreased levels of CD62L in the morbidly obese neutrophil pool possibly affect the neutrophil's ability to activate and migrate to sites of inflammation. This may play a role in the higher incidence of infectious complications seen in morbidly obese individuals.

Platelet and leukocyte activation correlate with the severity of septic organ dysfunction.

This study was conducted to investigate the extent of platelet-leukocyte adhesion and platelet, monocyte, and neutrophil activation in septic patients and to analyze whether these variables correlate with the severity of sepsis. Forty-seven patients consecutively admitted to the operative ICU of a University Medical Centre and 12 control patients prior to elective surgery were included in this prospective cohort study. Patients were evaluated daily for sepsis criteria and sepsis-associated organ failure assessment (SOFA) score was used to describe the extent of sepsis-associated organ failure. Indicators for cell activation (CD62P on platelets and CD11b on neutrophils and monocytes) and binding of platelets to neutrophils and monocytes were analyzed by flow cytometry. CD62P was increased on platelets from patients with sepsis compared with patients who did not have sepsis. Patients with sepsis also had higher CD11b expression on neutrophils and monocytes. Statistical analyses revealed a positive correlation between platelet CD62P expression and severity of sepsis, as well as a positive correlation between the SOFA score and CD11b on monocytes. No correlation was found between the SOFA score and CD11b on neutrophils. Higher values for platelet-neutrophil adhesion were observed in patients with uncomplicated sepsis compared either with controls or to patients with septic shock. An inverse relation between severity of sepsis and extent of platelet-neutrophil adhesion was also obvious from correlation analysis. The results indicate that flow cytometry can be used to measure these parameters of cell activation in sepsis and that activation of platelets and monocytes as well as adhesion of platelets to neutrophils does play a role in the development of organ dysfunction.