Leukocyte Plasma Research Articles

Nitrite levels in breath condensate of patients with cystic fibrosis is elevated in contrast to exhaled nitric oxide

BACKGROUNDNitric oxide (NO) is released by activated macrophages, neutrophils, and stimulated bronchial epithelial cells. Exhaled NO has been shown to be increased in patients with asthma and has been put...

Aprotinin complements heparin bonding in an in vitro model of cardiopulmonary bypass

The relative contribution of full-dose aprotinin, used with heparin-bonded surfaces, to contact activation during cardiopulmonary bypass was examined. In vitro Carmeda-bonded cardiopulmonary bypass circuits were perfused with whole blood anticoagulated with heparin (3.3 U/ml). Aprotinin (300 kIU/ml) was added to the circuits of one set of experiments. Samples were taken prior to perfusion and at 30, 60, 120 and 360 min. The activated coagulation time was extended in the aprotinin experiments, significantly at 30 min (P=0.003) and 120 min (P=0.001). Thrombin-antithrombin complexes and prothrombin fragment F1+2 were both higher in the non-aprotinin experiments at 120 min (P=0.02 each) and 360 min (P=0.005 and 0.001, respectively). Plasma leucocyte elastase was raised in the non-aprotinin experiments in comparison to the aprotinin experiments at each timepoint (30 min, P=0.04; 60 min, P=0.006; 120 min, P=0.001; 360 min, P=0.0001), as was interleukin-8 at 120 min (P=0.05) and 360 min (P=0.0001). No differences were found for the platelet activation marker P-selectin. Platelet and white blood cell counts fell significantly in the non-aprotinin experiments compared with the aprotinin experiments at 360 min (P=0.05 and 0.03, respectively). It would appear that the use of aprotinin has additional haemostatic beneficial effects to those found with heparin-bonded circuits in terms of effects on contact activation and inflammation.

Changes in donor leukocytes during blood storage. Implications on post-transfusion immunomodulation and transfusion-associated GVHD.

Freshly drawn peripheral blood granulocytes, monocytes and NK cells express Fas-L following activation. Fully functional soluble Fas-L (sFas-L) is released and found in fresh plasma samples from healthy volunteers coupled to a Fas-L binding factor (PFBF). In the absence of plasma leukocytes undergo rapid apoptosis with 15% of the granulocytes and 25% of the monocytes showing signs of apoptosis immediately following separation. Apoptosis progresses during refrigerated storage even in the presence of plasma and all granulocytes disintegrate by day 15 of storage. The absence of plasma increases the rate of apoptosis. The resulting increased expression of PS on apoptosing leukocytes enhances blood procoagulant activity. Whereas transfusions of fresh blood lead to alloimmunization, the functional impairment and death of antigen-presenting cells during storage eliminates their ability to stimulate cytotoxic immune responses. Additionally, loss of function and death of donor T cells during storage preclude the possibility for development of post-transfusion GVHD. Continued storage leads to the secondary necrosis of apoptosed leukocytes and the release of soluble antigens. Depending on dose, transfusion of such products may lead to immunosuppression due to a T2 bias of the immune response.

Proinflammatory cytokine release during pediatric cardiopulmonary bypass: Influence of centrifugal and roller pumps

Objective: It has been proposed that nonocclusive centrifugal pumps may elicit less blood cell trauma and hence a reduced inflammatory response than standard roller pumps. However, there have been no reports describing the impact of such pumps on proinflammatory cytokine release in pediatric cohorts. Design: A prospective randomized study was undertaken. Setting: A regional cardiothoracic center of a university hospital. Participants: Thirty-four pediatric patients undergoing cardiopulmonary bypass (CPB) for the correction of complex congenital heart defects were recruited. Interventions: Either standard twin roller (n = 17), or centrifugal vortex (Biopump, Medtronic Biomedicus Inc, MN) (n = 17) blood pumping. Measurements and Main Results: Venous blood was drawn (1) on induction of anesthesia, (2) 5 minutes on bypass, (3) end of CPB, (4) 30 minutes post-protamine, (5) 2 hours and (6) 24 hours postoperation. Neutrophil count, level of plasma leukocyte elastase, terminal complement complex (C5b-9), interleukin-6 (IL-6) and interleukin-8 (IL-8) were increased during and after CPB compared with the postinduction baseline. C5b-9 levels in both groups peaked at the end of CPB before returning to baseline at 24 hours: (median [range]), 564 (16 to 1,136) ng/mL in centrifugal group versus 508 (0 to 1,128) ng/mL in the roller group. IL-6 in both groups reached its peak level at 2 hours postprotamine (208 [98 to 411] pg/mL in centrifugal versus 205 [60–327] pg/mL in the roller group), before coming back to baseline at 24 hours. Plasma leukocyte elastase and IL-8 reached their maximum level 15 minutes after protamine administration: 215 (64 to 375) pg/mL in centrifugal versus 235 (87 to 410) pg/mL in roller group; and 700 (90 to 5,925) ng/mL versus 362 (120 to 3,400) ng/mL, respectively. Conclusions: The current study confirms the proinflammatory nature of pediatric CPB surgery, but failed to show a significant advantage of centrifugal pumping over roller perfusion in terms of the inflammatory response.

Salmeterol reduces early- and late-phase plasma leakage and leukocyte adhesion in rat airways.

We examined the effect of salmeterol, a long-acting beta2-adrenergic receptor agonist, on ovalbumin-induced plasma leakage and leukocyte adhesion in tracheal blood vessels of unanesthetized brown Norway rats. Ovalbumin challenge of sensitized rats resulted in both early and late phases of plasma leakage as measured with Evans blue. The early phase occurred during the challenge. The late phase began 2 h after the challenge, peaked at 4 h, and ended by 24 h. Ovalbumin challenge also increased the number of adherent leukocytes in mucosal blood vessels at 4 h. Nebulized salmeterol (5 mg/ml for 10 min) administered before the challenge inhibited the early-phase leak by 26%, 58%, or 85%, depending upon whether the interval between pretreatment and challenge was 0.5, 1, or 4.5 h, respectively. Similarly, salmeterol pretreatment (0.05 to 5 mg/ml for 10 min) reduced the late-phase leak at 4 h. Late-phase leakage was completely blocked at concentrations of 0.5 mg/ml or greater. This inhibitory effect was prevented by prior injection of the beta2-adrenergic receptor antagonist ICI-118,551. Salmeterol pretreatment also reduced the adherence of neutrophils, eosinophils, monocytes, and lymphocytes in mucosal blood vessels at 4 h. We conclude that salmeterol pretreatment can reduce the plasma leakage and leukocyte adhesion in early- and late-phase responses after antigen challenge through its action on beta2 receptors.

Utility of urine and leukocyte cultures and plasma DNA polymerase chain reaction for identification of AIDS patients at risk for developing human cytomegalovirus disease.

Urine and blood leukocyte cultures and qualitative plasma polymerase chain reaction (PCR) and quantitative competitive (QC) PCR were evaluated for their ability to identify AIDS patients at risk for human cytomegalovirus (HCMV) disease. AIDS patients were followed with urine and blood specimens every 3 months. During a mean follow-up of 12 months, 26 (28%) developed HCMV disease. The sensitivity, specificity, positive predictive value, and negative predictive value for urine culture were 85%, 29%, 31%, and 83%; for leukocyte culture were 38%, 74%, 69%, and 81%; for qualitative plasma PCR were 89%, 75%, 58%, and 94%; for QC-PCR (>1000 copies/microL) were 35%, 100%, 100%, and 80%; and for QC-PCR (>100 copies/microL) were 73%, 90%, 73%, and 90%, respectively. Of 41 patients identified by qualitative PCR to have HCMV DNA in plasma, the 24 who developed HCMV disease had 1510 +/- 448 (mean +/- SE) peak copies of HCMV DNA/microL by QC-PCR, versus 161 +/- 52 for the 17 patients who did not develop disease (P = .0007). Thus, plasma PCR is superior to culture for identification of AIDS patients at risk for HCMV disease, and quantitation of plasma DNA further identifies high-risk persons.

Histamine and Eicosanoid Levels in Plasma and Peripheral Blood Leucocyte Cultures During Experimental Infection of Cattle with Bluetongue Virus Serotype 11

Three calves were sensitized with three doses of inactivated BTV-11 UC8 strain and then experimentally infected with the homologous virus. In addition, four BTV-seronegative heifers were also experimentally infected with BTV-11. Granulocyte rich fractions of peripheral blood leucocyte (PBL-GRF) cultures from BTV-sensitized/infected calves and from control unexposed cattle were exposed in vitro with BTV-11. Histamine, leukotriene (LT) C4 and prostaglandin (PG) D2 were assayed in supernatant fluids. Plasma histamine levels increased in BTV-infected heifers from 10.1 +/- 2 ng/ml at Day 0 to 23.1 +/- 6.6 ng/ml at Day 12 following virus exposure. In addition, in this experimental group the concentration of PGF2 alpha (mean 551.97 +/- 243.54 pg/ml) increased significantly (P < or = 0.05) compared with control cattle (mean 467.3 +/- 73.9 pg/ml). Bluetongue virus induced histamine and LTC4 release after in vitro infection of PBL-GRF. Release of LTC4 was significantly (P < or = 0.05) higher in PBL-GRF cultures from sensitized and control animals than in unexposed PBL-GRF cultures. In contrast to these results, PGD2 was not released after BTV infection of PBL-GRF in vitro. The histamine release caused by BTV was virus-specific and mainly mediated by an immunological reaction, since the release was significantly reduced by removal of cell surface immunoglobulins.

Variation in Plasma Fibrinogen over One Year: Relationships with Genetic Polymorphisms and Non-genetic Factors

We analyzed plasma fibrinogen level in relation to genetic polymorphisms in the alpha- and beta-fibrinogen gene loci. Furthermore, the association of other CVD risk markers with fibrinogen was studied twice, with a time interval of one year in 50 to 60 year old men (n = 183). DNA polymorphisms were detected by PCR and digestion with Taq I (alpha-fibrinogen), Hind III and Bcl I (beta-fibrinogen) restriction enzymes. The correlation coefficient between fibrinogen measurements was 0.48 (p < 0.001). Blood leucocytes and waist-to-hip circumference ratio were the strongest correlates of fibrinogen level in both examinations, and the changes in leucocyte count and plasma fibrinogen correlated positively (r = 0.40, p < 0.001). In Eastern Finnish men, the Taq I, Hind III or Bcl I restriction fragment length polymorphisms of the alpha- or beta-fibrinogen gene loci did not associate with fibrinogen level, either cross-sectionally or longitudinally.

Influence of heparin thromboprophylaxis on plasma leucocyte elastase levels following lobectomy for lung carcinoma

Influence of heparin thromboprophylaxis on plasma leucocyte elastase levels following lobectomy for lung carcinoma

Does determination of tissue platinum levels by mass spectroscopy have potential for monitoring exposure of pharmacy personnel to platinum-based antineoplastic drugs? A pilot study

The mutagenic and carcinogenic properties of cyto toxic drugs have led to concern over potential haz ards to pharmacy personnel who are required to prepare cytotoxic drugs. The platinum compounds cisplatin and carboplatin are frequently used antican cer agents and are unique by virtue of their suitability for quantification by highly sensitive physical meth ods such as inductively coupled plasma mass spec troscopy (ICPMS). We have performed a pilot study of ICPMS determination of platinum levels in biological samples from pharmacists preparing chemotherapy, including platinum-based antineoplastic drugs. In pa tients treated with platinum compounds, elemental platinum was readily detected in plasma and whole leukocytes and bound to leukocyte DNA for at least 4 weeks after treatment. However, in 28 pharmacists from our institution (18 involved in preparation of platinum-based compounds, 10 controls), tissue plat inum levels were below the limit of detection (0.05 nmol/L) by ICPMS. ICPMS measurement of platinum levels has the potential to be used to monitor health care workers for exposure to platinum-based cytotox ics. Exposure may result from accidental exposure to a platinum-based compound or may be due to poor technique by personnel preparing chemotherapy doses. We are intending to institute a prospective monitoring policy to gather further data.

Cholesterol content of circulating immune complexes in patients with coronary stenosis and subjects without evidence of atherosclerosis

The biological variation factors for cholesterol in circulating immune complexes (CIC-cholesterol) were studied in 941 unselected supposedly healthy volunteers, ages 4 to 78 years. We found a complex effect of age, including the existence of two peaks of CIC-cholesterol, one in males between 11 and 14 years and in females between 11 and 30 years, and in both sexes another peak between 41 and 60 years, and in both sexes a decrease between 31 and 40 years. By use of multiple regression analysis and after adjustment for age, CIC-cholesterol was positively related to plasma cholesterol concentration and leukocyte count, values being lower in females than in males and among subjects taking anti-inflammatory drugs. In addition, CIC-cholesterol was measured in 76 coronary angiography patients and in 100 supposedly healthy controls, ages 30 to 77 years. We noticed a significant increase (P < or = 0.05) of CIC-cholesterol when patients were affected by coronary stenosis between 20% and 50% (71.8 +/- 52.5 mumol/L vs 46.2 +/- 45.9 mumol/L in controls), but this was less pronounced in those with > 50% of obstruction (58.9 +/- 54.3 mumol/L); however, serum total cholesterol was not modified or even surprisingly slightly decreased in the coronary angiography individuals. Nevertheless, an important overlap of values in controls and patients makes questionable the usefulness of this variable in clinical practice.

Influence of heparin thromboprophylaxis on plasma leucocyte elastase levels following lobectomy for lung carcinoma.

Recent in vitro studies and animal investigation indicate that plasma leucocyte elastase (PLE) can dissolve pulmonary structural proteins, such as elastin, and produce lesions in the lung similar to that seen in adult respiratory distress syndrome (ARDS) and emphysema. In contrast, heparin strongly inhibits PLE and protects elastin from elastolysis. On the basis of these findings, PLE levels were monitored in 24 patients with non-small cell lung carcinoma (NSCLC) undergoing lobectomy. Ten patients from Killingbeck Hospital (Group 1) received 5000 IU subcutaneous (s.c.) heparin commenced 2 h prior to surgery and continued at 8 h intervals until the patient was fully ambulatory. Fourteen patients from Bradford Royal Infirmary (Group 2) received no heparin as standard policy. There was no significant difference in pre-operative PLE levels between groups. The post operative PLE levels in both groups increased significantly (P < 0.02) on the first post operation day (POD). However, PLE levels of Group 2 were 2.5 to 5.3 times higher than those of Group 1 at each postoperative interval (first, third, and seventh POD) respectively (0.002 < P < 0.02). There was no difference in blood loss between groups (P = 0.17). These results indicate that post operative PLE activity is elevated in NSCLC patients following lobectomy and s.c. heparin administration as thromboprophylaxis may inhibit PLE activity post operatively without increasing blood loss. Therefore, heparin may have a role to play in protecting lung tissue against the pulmonary lesions caused by proteolytic activity of PLE, and theoretically reduce post-operative complications, such as ARDS or emphysema.

Modification of low density lipoproteins by plasma kallikrein, leukocyte elastase and cathepsin-G

Modification of low density lipoproteins by plasma kallikrein, leukocyte elastase and cathepsin-G

Plasma leukocyte elastase concentration in angiographically diagnosed coronary artery disease.

To evaluate the clinical usefulness of leukocyte elastase determination in the diagnosis of coronary artery disease (CAD). Recent research has shown the important role of elastase, a proteolytic enzyme released by neutrophils, in the pathogenesis of CAD. 141 patients underwent coronary angiography during investigation of chest pain and/or heart valve disease. Ninety-six had coronary lesions and 45 non-stenotic coronaries. The patients were characterized as regards presence or absence of angina (stable or unstable), family history of CAD, smoking, diabetes mellitus, hypertension, leukocyte counts, and plasma lipid and elastase concentrations. Among CAD-group patients, those with simple atheromatous plaques were distinguished from those with complex plaques. Elastase concentrations were greater in the CAD group than in the non-CAD group (49.7 +/- 2.8 micrograms.l-1; as against 29.5 +/- 2.2 micrograms.l-1; P < 0.001), and greater among complex-plaque CAD patients than among simple-plaque CAD patients (65.2 +/- 5.3 micrograms.l-1 as against 38.6 +/- 1.9 micrograms.l-1; P < 0.001). Logistic regression analysis showed (a) that the risk of CAD varied with elastase concentration, angina status, age and sex, increasing by 11% for every 1 microgram.l-1 increase in elastase concentration; and (b) that among CAD patients the risk of complex plaques was greatest for those with unstable angina and high elastase concentration, increasing by 6% for every 1 microgram.l-1 increase in elastase concentration. Peripheral blood leukocyte elastase concentration is a sensitive diagnostic marker of CAD. High values suggest the presence of complex atheromatous plaques.

Effects of plasma cortisol and its receptor on patients with deficiency-cold and deficiency-heat syndromes

Plasma cortisol levels and leukocyte glucocorticosteroid receptor (GCR) contents were assayed in 10 patients with Deficiency-Cold Syndrome, 10 patients with Deficiency-Heat Syndrome, and 10 healthy subjects as normal control. The results showed practically normal plasma cortisol levels in the Deficiency-Cold Group, but the leukocyte GCR contents were markedly lowered. In the Deficiency-Heat group, plasma cortisol levels were remarkably elevated and the leukocyte GCR contents also tended to be higher than normal. The quantity of plasma cortisol concentrations multiplied by leukocyte GCR contents can be taken as a sensitive index for the differentiation of Cold and Heat natures in Deficiency Syndromes.

Relationships between plasma cytokine concentrations and leukocyte functional antigen expression in patients with sepsis

To determine the relationships between cytokine concentrations and alterations in leukocyte functional antigen expression in sepsis. Prospective, cross-sectional study. Respiratory, coronary, and medical intensive care units in a university hospital. Forty subjects consisting of: a) patients with severe sepsis, b) patients with sepsis, c) critically ill nonseptic patients, and d) normal controls. None. Plasma concentrations of interleukin (IL)-1 beta, IL-6, IL-8, IL-10, interleukin-1 receptor antagonist (IL-1Ra), and tumor necrosis factor (TNF)-alpha were determined by enzyme-linked immunosorbent assay (ELISA). Peripheral blood monocyte HLA-DR and CD14 expression and neutrophil CD11b expression were determined by flow cytometry. Measurements were taken within 24 hrs of admission to the intensive care unit and/or clinical presentation. Significantly increased plasma IL-6, IL-8, IL-10, and TNF-alpha concentrations were observed in the severe sepsis group compared to normal controls. Increases in IL-1Ra were not significant. Monocyte HLA-DR expression, significantly decreased in patients with severe sepsis, was correlated both with IL-6 (p < .005) and IL-8 concentrations (p < .001). Both of these cytokines had close correlations to Acute Physiology and Chronic Health Evaluation (APACHE) II scores which were also correlated with monocyte HLA-DR. Neutrophil CD11b, which was increased in all infected patients, was significantly correlated with the ratio between IL-1 and IL-1Ra concentrations (p < .001). The percent of CD14+ monocytes was lowest in patients with severe sepsis and showed a significant covariate effect from IL-8 concentrations (p < .001). These findings suggest that the expression of specific functional molecules on peripheral blood leukocytes is variably related to the net production of certain monokines in sepsis.

Pig plasma modulates cell cycle kinetics but not the baseline frequency of sister-chromatid exhanges in human lymphocytes

The effect of human and pig plasma on the baseline frequency of sister-chromatid exchanges (SECs) in human and porcine plasma leukocyte cultures was studied. Human plasma leukocyte cultures, but not porcine plasma leukocyte cultures, showed at least a twofold increase in SCE frequency over whole blood culture values. Addition of pig plasma to human plasma leukocyte cultures and human plasma to pig plasma leukocyte cultures did not modify the baseline SCE frequencies. In both human and porcine cultures, cell proliferation was slower in plasma leukocyte cultures than in whole blood cultures. The addition of pig plasma to human plasma leukocyte cultures, but not the incorporation of human plasma in pig plasma leukocyte cultures, accelerated the cell cycle progression of lymphocytes. With 10% pig plasma in the plasma leukocyte culture medium, lymphocyte proliferation was similar to that in whole blood cultures. Smaller concentrations of pig plasma rendered cell cycle progression intermediate between the basal plasma leukocyte culture and whole blood culture values. Exchanging fetal calf serum for human AB serum in human plasma leukocyte cultures did not affect the cell cycle kinetics of lymphocytes but it did decrease their baseline SCE frequency.

Déleucocytation des produits sanguins et infections post-transfusionnelles

The transmission of unwanted infection agents to patients, through white blood cells, in blood products is now well established. Therefore the leukodepletion procedure undertaken in blood banks is justified. Leukodepletion prior to transfusion prevents the transmission of leukocyte-associated viruses such as CMV, EBV and HTLV 1 and 2 of viruses present both in plasma and inside leukocytes such as HTLV 1 and 2 viruses and B 19 parvovirus. The mechanism of the immunosuppressive effect of transfusion is still uncertain. The risks of transmitting bacterial diseases through blood transfusions is also a well-known source of concern, particularly the transmission of Yersinia Enterocolitica. However such an event seems to be prevented through leukocyte depletion by filtration when these procedures are performed after a hold of whole blood at 22 degrees C for 6 to no longer than 24 hours. Leukocyte-free blood components prepared by filtration may have a sufficiently reduced rate of infection to provide adequate prophylaxis. In any case the final number of leukocytes should be < or = 10(6) per unit of blood product. Leukocyte filtration must be performed before the onset of a disintegration process of granulocytes.

Febrile and metabolic tolerance to endotoxin and human recombinant interleukin-1 beta in rabbits

We investigated whether or not tolerance of the febrile and metabolic responses to human recombinant interleukin-1 beta (IL-1 beta) develops in rabbits. Febrile tolerance to bacterial endotoxin was induced by daily injections of lipopolysaccharide (LPS, 5.0 micrograms/kg iv). In LPS-tolerant rabbits, the second phase of the biphasic fever induced by intravenous injections of LPS (5.0 micrograms/kg) or IL-1 beta (2.0 micrograms/kg) was significantly reduced. However, the first phase was almost the same as that observed in normal rabbits. Five daily injections of IL-1 beta (2.0 micrograms/kg iv) resulted in the development of tolerance of the febrile response to IL-1 beta. In IL-1 beta-tolerant rabbits, the second peak of the biphasic fever was significantly reduced. In addition, decreases in leukocyte count and plasma zinc induced by intravenous injections of LPS or IL-1 beta were significantly reduced in LPS- or IL-1 beta-tolerant rabbits. However the monophasic fever induced by a smaller dose of IL-1 beta (0.5 microgram/kg iv) and the first peak of the IL-1 biphasic fever were almost the same as those observed in normal rabbits. Febrile responses induced in LPS- or IL-1 beta-tolerant rabbits by intracerebroventricular injections of LPS (5.0 ng) or IL-1 beta (2.0 ng) were similar to those observed in normal rabbits. The present results suggest that tolerance of the febrile and metabolic responses to IL-1 beta is developed after repeated injections of IL-1 beta and that reduced responsiveness to IL-1 beta is partly involved in the development of LPS tolerance.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood viscosity, fibrinogen, and activation of coagulation and leukocytes in peripheral arterial disease and the normal population in the Edinburgh Artery Study.

Increased blood and plasma viscosity, hematocrit, fibrinogen, and activation of coagulation and leukocytes have been reported in patients with claudication; however, their associations with symptomatic and asymptomatic peripheral arterial disease have not been reported in an epidemiological study. Blood and plasma viscosity, hematocrit, fibrinogen, urinary fibrinopeptide A, plasma leukocyte elastase, and uric acid were measured in a random sample of 1,581 men and women aged 55-74 years in Edinburgh, Scotland, and related to peripheral arterial stenosis (ankle-brachial systolic pressure index, ABPI) and to lower limb ischemia (intermittent claudication and reactive hyperemia test). Each variable (except fibrinopeptide A) was significantly related to prevalent symptomatic and asymptomatic peripheral arterial disease. On multivariate analysis, blood viscosity (p < 0.05) and fibrinogen (p < 0.01) were independently associated with peripheral arterial narrowing (ABPI); a positive interaction was found between fibrinogen and smoking in the association with ABPI. Plasma viscosity was associated with claudication in the presence of a given degree of arterial narrowing (odds ratio of claudication in top quintile compared with bottom quintile of plasma viscosity, 3.35; 95% CI, 1.32, 8.51). Leukocyte elastase and uric acid were each associated with reactive hyperemia independently of arterial narrowing (p < 0.01). Blood rheological factors and leukocyte activation as well as arterial narrowing are associated with lower limb ischemia in the general population and may be implicated in its pathogenesis.