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Biomedical subjects

W Speiser

Publications and source records attributed to W Speiser.

At least 19 recordsLinked to original sources

High plasma levels of factor VIII and the risk of recurrent venous thromboembolism.

BACKGROUND: A high plasma level of factor VIII is a risk factor for venous thromboembolism. We evaluated the risk of a recurrence of thrombosis after an initial episode of spontaneous venous thromboembolism among patients with high plasma levels of factor VIII. METHODS: We studied 360 patients for an average follow-up period of 30 months after a first episode of venous thromboembolism and discontinuation of oral anticoagulants. Patients who had recurrent or secondary venous thromboembolism, a congenital deficiency of an anticoagulant, the lupus anticoagulant, hyperhomocysteinemia, cancer, or a requirement for long-term treatment with antithrombotic drugs or who were pregnant were excluded. The end point was objectively documented, symptomatic recurrent venous thromboembolism. RESULTS: Recurrent venous thromboembolism developed in 38 of the 360 patients (10.6 percent). Patients with recurrence had higher mean (+/-SD) plasma levels of factor VIII than those without recurrence (182+/-66 vs. 157+/-54 IU per deciliter, P=0.009). The relative risk of recurrent venous thrombosis was 1.08 (95 percent confidence interval, 1.04 to 1.12; P<0.001) for each increase of 10 IU per deciliter in the plasma level of factor VIII. Among patients with a factor VIII level above the 90th percentile of the values in the study population, the likelihood of recurrence at two years was 37 percent, as compared with a 5 percent likelihood among patients with lower levels (P<0.001). Among patients with plasma factor VIII levels above the 90th percentile, as compared with those with lower levels, the overall relative risk of recurrence was 6.7 (95 percent confidence interval, 3.0 to 14.8) after adjustment for age, sex, the presence or absence of factor V Leiden or the G20210A prothrombin mutation, and the duration of oral anticoagulation. CONCLUSIONS: Patients with a high plasma level of factor VIII have an increased risk of recurrent venous thromboembolism.

Factor VIII↗

The salicylate metabolite gentisic acid, but not the parent drug, inhibits glucose autoxidation-mediated atherogenic modification of low density lipoprotein.

Oxidation of low density lipoprotein (LDL) by glucose-derived radicals may play a role in the aetiology of atherosclerosis in diabetes. Salicylate was shown to scavenge certain radicals. In the present study, aspirin, salicylate and its metabolites 2,5- and 2, 3-dihydroxybenzoic acid (DHBA) were tested for their ability to impair LDL oxidation by glucose. Only the DHBA derivatives, when present during LDL modification, inhibited LDL oxidation and the increase in endothelial tissue factor synthesis induced by glucose oxidised LDL. The LDL glycation reaction was not affected by DHBA. The antioxidative action of DHBA may be attributed to free radical scavenging and/or chelation of transition metal ions catalysing glucose autoxidation.

Arteriosclerosis↗

Lepirudin blunts endotoxin-induced coagulation activation.

During sepsis, lipopolysaccharide (LPS) triggers the development of disseminated intravascular coagulation (DIC) via the tissue factor-dependent pathway of coagulation resulting in massive thrombin generation and fibrin polymerization. Recently, animal studies demonstrated that hirudin reduced fibrin deposition in liver and kidney and decreased mortality in LPS-induced DIC. Accordingly, the effects of recombinant hirudin (lepirudin) was compared with those caused by placebo on LPS-induced coagulation in humans. Twenty-four healthy male subjects participated in this randomized, double-blind, placebo-controlled, parallel group study. Volunteers received 2 ng/kg LPS intravenously, followed by a bolus-primed continuous infusion of placebo or lepirudin (Refludan, bolus: 0.1 mg/kg, infusion: 0.1 mg/kg/h for 5 hours) to achieve a 2-fold prolongation of the activated partial thromboplastin time (aPTT). LPS infusion enhanced thrombin activity as evidenced by a 20-fold increase of thrombin-antithrombin complexes (TAT), a 6-fold increase of polymerized soluble fibrin, termed thrombus precursor protein (TpP), and a 4-fold increase in D-dimer. In the lepirudin group, TAT increased only 5-fold, TpP increased by only 50%, and D-dimer only slightly exceeded baseline values (P <.01 versus placebo). Concomitantly, lepirudin also blunted thrombin generation evidenced by an attenuated rise in prothrombin fragment levels (F(1 + 2), P <. 01 versus placebo) and blunted the expression of tissue factor on circulating monocytes. This experimental model proved the anticoagulatory potency of lepirudin in LPS-induced coagulation activation. Results from this trial provide a rationale for a randomized clinical trial on the efficacy of lepirudin in DIC. (Blood. 2000;95:1729-1734)

Adult↗

Thrombus formation on the balloon of heparin-bonded pulmonary artery catheters: an ultrastructural scanning electron microscope study.

OBJECTIVE: To investigate heparin-bonded pulmonary artery catheters with respect to thrombus formation and platelet aggregation at the balloon and the shaft using a scanning electron microscope in critically ill patients. DESIGN: Prospective study. SETTINGS: Critical care unit and research laboratories. PATIENTS: Pulmonary artery catheters were inserted in critically ill patients (n = 10). INTERVENTIONS: Pulmonary artery catheters were removed after 24, 48, 72, or 120 hrs, and the ultrastructure was investigated in specialized research laboratories. MEASUREMENTS AND MAIN RESULTS: Balloon and shaft were investigated using a scanning electron microscopic technique. Area of thrombus formation was quantified using image analysis. Heparin release of the catheters was measured. The frequency of balloon inflations was investigated in in vitro experiments by inflating catheters different times (0, 10, 20, and 30 times). Twenty-four hours after catheter insertion, scanning electron microscopic images showed thrombus formation and platelet aggregation at the site of the balloon. Seventy-two hours after catheter insertion, a thrombus started to detach. The areas of thrombus formation did not differ, but thrombus organization changed dramatically 72 and 120 hrs after catheter insertion. The shaft was colonized by single cells only. Cracks of the balloon could be observed after 72 hrs, whereas no cracks could be found in in vitro controls. In vitro, heparin release of the pulmonary artery catheters decreased significantly after 24 hrs. CONCLUSIONS: Scanning electron microscopic images of heparin-bonded pulmonary artery catheters demonstrate thrombus formation on the balloon 24 hrs after pulmonary artery catheter insertion, increasing dramatically at 72 and 120 hrs. The shaft was colonized by single cells only. The thrombus size is not significantly different during the observation time, but the grade and quality of thrombus formation differ.

Anticoagulants↗

Endothelin 1 transcription is controlled by nuclear factor-kappaB in AGE-stimulated cultured endothelial cells.

Incubation of bovine aortic endothelial cells (BAECs) with erythrocytes from patients with type 2 diabetes induced an increase in endothelin 1 (ET-1) production. The effect of erythrocytes on ET-1 synthesis was dependent on glycemic control. ET-1 levels after incubation with erythrocytes derived from patients with HbA(1c) levels <6% were just half the levels observed after incubation with erythrocytes from patients with HbA(1c) levels >8%. Nepsilon-(carboxymethyl)lysine (CML)-containing protein isolated from patients' erythrocytes induced ET-1, and CML-containing protein-dependent ET-1 induction was blocked by the recombinant decoy peptide soluble receptor for advanced glycation end products (AGEs), which comprises the NH2-terminal Ig domain of the receptor for AGEs. In vitro-generated AGEs induced ET-1 mRNA transcription (nuclear run-on assay and Northern blot) in a time- and dose-dependent manner. Transient transfection of BAECs with a chimeric construct containing the 5' promoter region of the ET-1 gene linked to a reporter gene confirmed that AGE induced ET-1 promoter activity. Electrophoretic mobility shift assay confirmed AGE-inducible binding of members of the nuclear factor-kappab (NF-kappaB) family to a potential binding site at -2,090 bp. Binding was functionally significant because overexpression of the cytoplasmic inhibitor of NF-kappaB or deletion of the NF-kappaB binding site reduced ET-1 induction, whereas overexpression of NF-kappaB p65 induced ET-1 even in the absence of AGEs. Thus, ET-1 transcription is controlled by the AGE-inducible redox-sensitive transcription factor NF-kappaB.

Animals↗

Monitoring of aspirin (ASA) pharmacodynamics with the platelet function analyzer PFA-100.

BACKGROUND: Anti-platelet drug therapy is currently performed without monitoring, because the established method of platelet aggregometry is cumbersome. The recently developed platelet function analyzer PFA-100 measures shear stress dependent, collagen epinephrine (CEPI) and collagen adenosine diphosphate (CADP) induced platelet plug formation. As the PFA-100 provides a valuable tool to detect patients with platelet dysfunction more efficiently and cost-effectively than aggregometry, we investigated its potential to monitor the efficacy of aspirin treatment. METHODS: All healthy volunteers (n = 10) received a fractionated infusion of L-aspirin to establish individual dose-response curves. Further, in a randomized, double-blind, placebo controlled two-way cross over study the same volunteers received either 50 or 100 mg aspirin/day p.o. for a period of 11 days to determine the day-to-day variability CEPI induced closure time (CT) under constant intake of low dose aspirin, and to compare the efficacy of those two doses. RESULTS: Intra- and intersubject variability of CEPI-CT averaged 9% and 22%, respectively. Seven volunteers exceeded the maximum of CEPI-CT (>300 s) already after infusion of 100 mg L-aspirin. Intake of 100 mg of aspirin elicited a more rapid onset of effect than 50 mg, which was only significant on days 3 and 4 of aspirin intake. The aspirin induced CEPI-CT prolongation correlated positively with basal CEPI-CT values (r = 0.86; p = 0.001) and were strongly dependent on von Willebrand Factor levels (r = -0.9; p = 0.001). CONCLUSION: Thus, the PFA-100 system appears suitable to demonstrate an aspirin-induced platelet effect in a longitudinal study, and may be adequate to monitor a patient's compliance. However, prospective trials have to be conducted to demonstrate whether the EPI-CT achieved under ASA-intake has predictive value for cardiovascular outcome.

Adenosine Diphosphate↗

Rapid, fluorescence-based assay for microtiter plates to test drug influences on neutrophil transmigration through endothelial cell monolayers.

Investigation of drug interactions between blood cells and endothelium is of high interest. The current study describes the development of a rapid fluorescence-based leukocyte transmigration system through endothelial cell monolayers for investigation of drug influences. To test the new assay, endothelial cells were cultured on microporous filters, pore size 3.0 microm, in 96-well-plates. Freshly isolated neutrophils were seeded on endothelial cell monolayers and transmigrated cells were measured after incubation for three hours. Migration of non-stimulated neutrophils through non-stimulated endothelial cell monolayer was used as control and set as 100%. The influence of the non-steroidal anti-inflammatory drug diclofenac was investigated. Assay precision tests were done using intraassay (within-day variability) and interassay (day-to-day variability) controls. Transmigration rate was decreased to 53 +/- 6.8% SD (diclofenac 0.7 microg/mL). Different concentrations showed a dose dependent effect (0.07 microg/mL: 97 +/- 9.5%, 7 microg/mL: 37 +/- 4.7%). Analysis of assay accuracy of the new 96-well-sized transmigration assay showed reliable results (coefficient of variation: intraassay 8.2 %; interassay 11.8%). In conclusion, this new, rapid, and sample saving 96-well-microtiter transmigration assay allows examination of drug influence on neutrophil migration through endothelial cell monolayers. Moreover, this assay can also be used for other cell-cell interactions.

Adult↗

The Factor V (Leiden) test: evaluation of an assay based on dilute Russell Viper Venom Time for the detection of the Factor V Leiden mutation.

In the present study a new clotting assay for the detection of an increased resistance of coagulation factor V against degradation by activated protein C (Factor V Leiden mutation, FVLM) was evaluated. The Factor V (Leiden) Test (Gradipore, North Ryde NSW, Australia) is based on the dilute Russell Viper Venom Time (DRVVT), which is prolonged when the plasma sample is preincubated with dilute whole Agkistrodon contortrix contortrix venom for activation of protein C (PC). In contrast to the DRVVT based global assay, Protein C Pathway Test (Gradipore, North Ryde NSW, Australia) this new assay is expected to be more specific for FVLM because of optimized amounts of the venom. The test result is expressed as the ratio between the DRVVT with and without addition of the venom. The following precision values were found: intraassay coefficient of variation (CV): 5.53% (n=20) in the normal range, 4.30% (n=20) in the pathological range; interassay CV: 6.90% (n=10) and 7.64% (n=10), respectively. A normal range (5th to 95th percentile) of 2.12 to 3.08 was calculated from 50 healthy controls. A ratio below 2.12 was found in all samples from patients with FVLM (n=21), in 9 of 12 patients with PC, in 0 of 6 with protein S (PS), and in 0 of 4 with antithrombin (AT) deficiency. There was, however, a good discrimination between carriers of the FVLM (highest ratio 1.44) and patients deficient in PC (lowest ratio 1.59), in particular when samples were prediluted with factor V deficient plasma FVDP (1.16 vs. 1.96, respectively). Predilution of samples with FVDP caused a clear discrimination between controls and patients deficient in PC, PS, AT, and FVLM-positive individuals and also in patients on oral anticoagulant treatment. Our data show that the Factor V (Leiden) Test discriminates well between carriers of the FVLM and healthy controls or patients deficient in PC, PS, and AT. Individuals presenting values between the lower cutoff of controls and the range in which FVLM-positive individuals are found are highly suspicious for protein C deficiency.

Antithrombins↗

Evaluation of the automated coagulation analyzer SYSMEX CA 6000.

In the present study the coagulation analyzer SYSMEX CA 6000 (TOA Medical Electronics Co., Kobe, Japan), an analyzer equipped with a photooptical clot detection unit and a cap-piercing system, was evaluated with respect to its technical characteristics in the determination of standard coagulation tests (prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen, and antithrombin) and in the determination of coagulation single factor activities. In the normal and in the pathological range the intraassay coefficients of variation (CV) and interassay CV for most parameters were below 5% (exceptions: intraassay CV 5.4% for prolonged thrombin time; intraassay CV 9.26% and interassay CV 10.7% for decreased antithrombin; interassay CV 5.62% for fibrinogen in the normal range, intraassay CV 10.1% for fibrinogen greater than 7.0 g/L; intraassay CV 6.36% and interassay CV 11.7% for decreased fibrinogen; interassay CV 11.6% for prolonged activated partial thromboplastin time; interassay CV 6.12% for decreased factor VII). Interference studies with lipemic, icteric, and hemolytic samples showed just minor influences of these abnormal sample characteristics on prothrombin time, activated partial thromboplastin time, fibrinogen, and antithrombin measurements when compared to the results obtained by using mechanical clot detection (STA, Stago Diagnostica, Asnieres-Sur-Seine, France). No carryover was detected in alternating measurements of heparinized (3 U/mL unfractionated heparin) and normal plasma samples. Measurement of the activities of clotting factors V, VII, VIII, and IX showed a good correlation (r=0.993 to r=0.977) between SYSMEX CA 6000 and STA. Our results demonstrate that using SYSMEX CA 6000 analyzer basal routine coagulation testing as well as specialized tests for single factor activities can be performed with satisfactory precision; in particular, the cap-piercing system has no negative effect on the performance of the analyzer.

Adult↗

The green tea extract epigallocatechin gallate is able to reduce neutrophil transmigration through monolayers of endothelial cells.

Green tea is widely used in Asia and has also become popular in Western countries. The influence of green tea extracts on leukocytes is not well understood. Leukocytes play a crucial role in the process of inflammation. They migrate from the intravascular space into the tissue to attack micro-organisms. The aim of the current study was to investigate the influence of epigallocatechin gallate on leukocyte transmigration through endothelial cell monolayers and thereby evaluate its potential role in the inflammatory process. Human umbilical vein endothelial cells were cultured on microporous membranes to achieve a monolayer. Freshly isolated neutrophils from healthy subjects were measured with a migration assay. The amount of untreated neutrophils migrating through untreated endothelial cell monolayers was used as control and set as 100%. Neutrophils and/or endothelial cell monolayers were pre-treated with epigallocatechin gallate using relevant, as well as higher and lower concentrations. The relevant plasma concentration of epigallocatechin gallate was able to significantly inhibit neutrophil migration through endothelial cell monolayers (69 +/- 6.4% SD; p < 0.05 compared to control), when both cell types (leukocytes and endothelial cell monolayer) were treated. This is similar to the situation after resorption in-vivo. Treating either neutrophils or endothelial cell monolayers alone led to significant reductions in migratory response (only neutrophils treated: 86 +/- 8.1% SD, p < 0.05; only endothelial cell monolayers: 77 +/- 6.1%, p < 0.05). In conclusion, epigallocatechin gallate was identified as a potent inhibitor of leukocyte migration through endothelial cell monolayers. The treatment of both cell types showed an additive effect. Endothelial cells seem to be more affected than neutrophils. Further clinical investigations are necessary to understand the potential clinical consequences.

Catechin↗

The mast cell as site of tissue-type plasminogen activator expression and fibrinolysis.

Recent data suggest that mast cells (MC) and their products (heparin, proteases) are involved in the regulation of coagulation and fibrino(geno)lysis. The key enzyme of fibrinolysis, plasmin, derives from its inactive progenitor, plasminogen, through catalytic action of plasminogen activators (PAs). In most cell systems, however, PAs are neutralized by plasminogen activator inhibitors (PAIs). We report that human tissue MC as well as the MC line HMC-1 constitutively produce, express, and release tissue-type plasminogen activator (tPA) without producing inhibitory PAIs. As assessed by Northern blotting, highly enriched lung MC (>98% pure) as well as HMC-1 expressed tPA mRNA, but did not express mRNA for PAI-1, PAI-2, or PAI-3. The tPA protein was detectable in MC-conditioned medium by Western blotting and immunoassay, and the MC agonist stem cell factor (c-Kit ligand) was found to promote the release of tPA from MC. In addition, MC-conditioned medium induced fibrin-independent plasmin generation as well as clot lysis in vitro. These observations raise the possibility that MC play an important role in endogenous fibrinolysis.

Cell Line↗

Dexamethasone inhibits leukocyte migration through endothelial cells towards smooth muscle cells.

Leukocyte interactions with endothelial cell monolayers (ECM) and smooth muscle cells (SMC) play an important role during inflammatory processes. Several studies describe an inhibitory effect of dexamethasone on polymorphonuclear leukocytes (PMNL), endothelial cell function, and interleukin-1 (IL-1) release. Aim of the current study was to investigate the influence of dexamethasone on leukocyte migration through an endothelial cell monolayer towards SMC-layers stimulated by tumor necrosis factor-alpha (TNF-alpha). Using a recently developed triple chamber migration system, SMC-layers were cultured on the bottom of a 24-well plate. On the upper surface of the first filter, ECM were cultured, the second filter was a collecting filter. The amount of leukocyte migration through ECM towards TNF-alpha-stimulated smooth muscle cell layers with and without dexamethasone-pretreatment was measured using a fluorescence technique. The pretreatment of SMC-layers with dexamethasone reduced the amount of leukocyte migration down to 92 +/- 8.8% (0.001 mM, p=n.s.), to 67 +/- 5.7% (0.01 mM, p<0.05), to 53 +/- 4.6% (0.1 mM, p<0.05), and to 41 +/- 5.0% (1 mM, p<0.05). In conclusion, dexamethasone treatment of smooth muscle cell layers inhibits leukocyte migration through ECM towards smooth muscle cell layers. The inhibition seems to be due to a decrease in IL-1 release. Treatment of all cell types, PMNL, endothelial cells, as well as smooth muscle cell layers, simulating an in-vivo situation, seems to have an additive effect.

Cell Culture Techniques↗

Heparin lowers plasma levels of activated factor VII.

Based on heparin's antithrombin and anti-FXa activity and its in vitro inhibition of activated factor VII (FVIIa) activity, we hypothesized that unfractionated heparin (UFH) may decrease plasma levels of FVIIa in humans. Therefore, 10 healthy young male volunteers received an intravenous UFH infusion over 24 h. Heparin decreased FVIIa levels by 30% (95% CI 14-47%) at 12 h, which was sustained until 24 h. In contrast, neither the substrate pool (i.e. total factor VII) as measured by FVII antigen nor FVII activity were affected by UFH. These results may improve our understanding of the regulation of FVIIa levels and heparin's mode of action.

Adult↗

Thromboembolism and resistance to activated protein C in patients with inflammatory bowel disease.

OBJECTIVE: Thromboembolic events are serious complications in patients with inflammatory bowel disease (IBD). Resistance of factor V to degradation by activated protein C (APC) is a major cause for venous thrombosis and is found in approximately 30% of patients with thromboembolism. The aim of the present study was to assess the prevalence of APC resistance and clinical risk factors in patients with IBD. METHODS: One-hundred-two patients with IBD (64 women and 38 men; median age, 35 yr; range, 17-77 yr; 77 with Crohn's disease, 25 with ulcerative colitis) and 102 gender- and age-matched healthy control subjects were investigated prospectively for the presence of APC resistance. None of the healthy controls but 16 patients with IBD had a history of thromboembolism. RESULTS: Patients with IBD and thromboembolism were young, with a median age of 37 yr (range, 17-61 yr). Five (31.3%) of them had APC resistance, which was more common than in patients with IBD without thromboembolism (7%) and in controls (5.9%) (p < 0.01). Three patients had two thromboembolic events, the other 13 each had one. Deep vein thrombosis of the leg and pulmonary emboli were the most common thromboembolic complications (84.2%). Active disease, fistula, or bowel stenosis were found in 10 (52.6%) of 19 thromboembolic events; in three (15.8%) cases thromboembolism happened postoperatively. CONCLUSIONS: APC resistance is not associated with IBD but, when present, increases the risk of thromboembolism. Patients with IBD and thromboembolism are mostly young and clinical risk factors can be found in one-half of cases.

Activated Protein C Resistance↗

Endotoxin-induced activation of the coagulation cascade in humans: effect of acetylsalicylic acid and acetaminophen.

During Gram-negative septic shock, lipopolysaccharide (LPS, endotoxin) induces tissue factor (TF) expression. TF expression is mediated by nuclear factor kappaB and amplified by activated platelets. TF forms a highly procoagulant complex with activated coagulation factor VII (FVIIa). Hence, we hypothesized that aspirin, which inhibits LPS-induced, nuclear factor kappaB-dependent TF expression in vitro and platelet activation in vivo, may suppress LPS-induced coagulation in humans. Therefore, we studied the effects of aspirin on systemic coagulation activation in the established and controlled setting of the human LPS model. Thirty healthy volunteers were challenged with LPS (4 ng/kg IV) after intake of either placebo or aspirin (1000 mg). Acetaminophen (1000 mg) was given to a third group to control for potential effects of antipyresis. Neither aspirin nor acetaminophen inhibited LPS-induced coagulation. However, LPS increased the percentage of circulating TF(+) monocytes by 2-fold. This increase was associated with a decrease in FVIIa levels, which reached a minimum of 50% 24 hours after LPS infusion. Furthermore, LPS-induced thrombin generation increased plasma levels of circulating polymerized, but not cross-linked, fibrin (ie, thrombus precursor protein), whereas levels of soluble fibrin were unaffected. In summary, a single 1000-mg dose of aspirin did not decrease LPS-induced coagulation. However, our study showed, for the first time, that LPS increases TF(+) monocytes, substantially decreases FVIIa levels, and enhances plasma levels of thrombus precursor protein, which may be a useful marker of fibrin formation in humans.

Acetaminophen↗

[Disseminated intravascular coagulation (DIG) with massive hyperfibrinolysis in metastatic uterine cancer. Observations on the effects on the coagulopathy of various treatments (a case report)].

We report on a 64-year-old patient with a recurrent endometrial carcinoma which was associated with disseminated intravascular coagulation (DIC) and excessive hyperfibrinolysis. The patient presented with severe bleeding due to hypofibrinogenemia. Fibrin degradation products were excessively elevated and there were also increased levels of activation markers of coagulation. Free plasmin was demonstrated in the circulation and alpha 2-antiplasmin was almost completely depleted. No increase in t-PA or u-PA level was demonstrated. Antifibrinolytic treatment led to a decrease of fibrin degradation products, but to an increase of activation markers of coagulation and was not associated with an increase of fibrinogen. Combination chemotherapy led to a rapid decrease of activation markers of coagulation and a sustained increase of fibrinogen. The beneficial effects on DIC/hyperfibrinolysis occurred despite the absence of any measurable effect of chemotherapy on the tumour. The patient finally died due to progression of the tumour, but without recurrence of the DIC/hyperfibrinolysis.

Adenocarcinoma↗

Ibuprofen inhibits leukocyte migration through endothelial cell monolayers.

During inflammation leukocytes are playing a tremendous role in the defense against bacterial infections. Tumor necrosis factor alpha (TNF alpha) increases adhesion of leukocytes to endothelial cells. The non steroidal anti-inflammatory drug ibuprofen is able to reduce inflammatory processes in humans and is a widely used drug. The influence of ibuprofen on TNF-alpha-induced expression of adhesion molecules on endothelial cells is well investigated and has been published recently by our group. For leukocyte migration, leukocytes have to attach and finally migrate through monolayers of endothelial cells. The aim of the current study was to investigate leukocyte migration through endothelial cell monolayers (ECM) under ibuprofen using a migration assay system. Ibuprofen was identified as a potent inhibitor of the leukocyte migration through endothelial cell monolayers in a dose dependent manner. The treatment of either leukocytes (87 +/- 17.6 %; p>0.05) or endothelial cell monolayers (62.5 +/- 9.4 %; p<0.05) showed that the influence is more mediated through endothelial cells, the treatment of both cell types demonstrated an additive effect. In conclusion, the previously published changes of adhesion molecules on endothelial cells could be confirmed with this functional migration test. The inhibition of the leukocyte migration may contribute to the anti-inflammatory actions of the drug.

Anti-Inflammatory Agents, Non-Steroidal↗