Elevated levels of soluble CD40 ligand are associated with antiphospholipid antibodies in patients with systemic lupus erythematosus.

OBJECTIVES: The CD40L/CD40 pathway is involved in the pathophysiology of atherothrombotic disease, and elevated levels of soluble CD40L (sCD40L) were reported in SLE patients. However, the clinical implication of sCD40L in SLE remains elusive. METHODS: We measured levels of plasma sCD40L in 241 SLE patients and 37 healthy controls and investigated its association with clinical manifestation and laboratory parameters. RESULTS: Levels of plasma sCD40L in SLE patients were significantly elevated compared with healthy controls (p=0.013) and positively correlated with levels of soluble P-selectin (γ=0.336, p<0.001). SLE patients who experienced arterial thrombosis had a higher level of sCD40L than those who did not (p=0.029). Plasma sCD40L levels were positively correlated with the titers of anti-cardiolipin and anti-ß2 glycoprotein I antibodies (γ=0.338, p<0.001 and γ=0.364, p<0.001, respectively). Its levels were also significantly higher in patients with clinical antiphospholipid syndrome (APS) than in non-APS patients, irrespective of antiphospholipid antibody (aPL) positivity. Of those with arterial thrombosis, sCD40L levels were significantly elevated in patients with positive aPL, compared to those with negative aPL (p=0.011). Multiple regression analysis revealed that the presence of hypertension and positive aPL were independently associated with the occurrence of arterial thrombosis in SLE patients. A parallel analysis showed that sCD40L was also an independent variable for arterial thrombosis; however, this association disappeared when aPL, a strong variable, was included in the model because of collinearity between aPL and sCD40L. CONCLUSIONS: Plasma sCD40L levels were elevated in SLE patients who had positive aPL and experienced arterial thrombosis, suggesting that enhanced release of sCD40L through platelet activation presumably by aPL could contribute to the development of atherothrombotic disease.

Neutrophil/Lymphocyte ratio and association with arch intervention in patients with hypoplastic left heart syndrome undergoing hybrid procedure.

BACKGROUND: Hybrid procedure is an alternative initial palliation for patients with hypoplastic left heart syndrome (HLHS). One major complication with this procedure is stenosis in the aortic arch isthmus possibly due to inflammation from the patent ductus arteriosus (PDA) stent. In adult studies, neutrophil/lymphocyte (N/L) ratio has been used as a marker for increased inflammation and has been associated with increased risk for coronary artery stent stenosis. The goal of this study was to determine if there were differences in N/L ratio between patients with HLHS undergoing hybrid procedure that required an arch intervention (AI-Group) vs. those that did not require an intervention (NAI-Group). METHODS: Retrospective chart review was performed on patients with HLHS undergoing hybrid procedure between July 2002 and January 2013. Complete blood counts as well as differentials were recorded at four time periods: 1 day prehybrid palliation, one day posthybrid palliation, 1 week posthybrid palliation, and 3 weeks posthybrid palliation. RESULTS: One hundred six patients were evaluated (AI-Group = 38, NAI-Group = 68). AI-Group generally had a higher N/L ratio vs. NAI-group and this was significant immediately 1 day posthybrid palliation: AI-Group vs. NAI-Group, prehybrid (2.95 ± 2.62 vs. 2.44 ± 1.71), 1 day posthybrid (5.95 ± 4.16 vs. 4.34 ± 3.87, P < .05), 1 week posthybrid (2.72 ± 3.01 vs. 2.28 ± 2.12), and 3 weeks posthybrid (1.85 ± 1.24 vs. 1.45 ± 1.16), respectively. Lymphocyte percentage was significantly lower in the AI-Group vs. NAI-Group 3 weeks posthybrid palliation (33.00 + 11.30% vs. 40.65 + 16.82%). CONCLUSION: Patients that required an arch intervention after hybrid palliation had a higher N/L ratio immediately after the procedure. This may signify increased inflammatory reaction that places these patients at risk for stenosis. Future studies are needed to determine if N/L ratio is a robust marker to risk stratify patients undergoing the hybrid procedure for arch complications.

Serial analysis of clinical and imaging indices reveals prolonged efficacy of TNF-α and IL-6 receptor targeted therapies in refractory Takayasu arteritis.

OBJECTIVES: We analysed a large cohort of patients with Takayasu arteritis, seeking robust clinical evidence for prolonged responses to tumour necrosis factor-α (TNF-α) and interleukin-6 receptor (IL-6R) antagonists in severe refractory disease. METHODS: Case notes from ninety-eight patients with Takayasu arteritis were retrospectively reviewed. Drug treatment, laboratory and serial non-invasive imaging data were analysed, and the Indian Takayasu arteritis activity (ITAS) and damage scores (TADs) calculated. RESULTS: Nine patients were treated with biologic therapies. All had previously received high dose prednisolone and ≥1 conventional immunosuppressant. Five patients had failed cyclophosphamide. The patients prescribed biologics had more extensive arterial injury than the remainder of the cohort and persistent active disease (ITAS range 2-9, CRP 12-206 mg/L, TADs 3--1). Eight patients were prescribed anti-TNF-α therapy, three IL-6R blockade. The mean duration of anti-TNF-α treatment was 42 months (maximum 8 years). One patient developed new arterial stenoses while receiving anti-TNF-α and subsequently achieved disease remission with tocilizumab. Two patients have now demonstrated sustained responses to IL-6R inhibition at 19 and 20 months. Following introduction of biologic therapy, serial non-invasive imaging has revealed no significant progression in arterial injury. A significant fall in CRP (p<0.01), prednisolone dose (p<0.01) and ITAS (p<0.01) was observed, with no increase in TADs. CONCLUSIONS: We report for the first time sustained responses to both anti-TNF-α and IL6R antagonists in refractory Takayasu arteritis. As 5/9 patients were cyclophosphamide non-responders, we propose that biologics should now be considered ahead of cyclophosphamide in these young patients.

Castleman's disease and arterial thrombosis: result of excessively elevated interleukin-6 plasma level?

Morbus Castleman is a benign non-clonal lymphoproliverative disorder. Immunomodulatory and antiproliferative drugs are used to treat this plasma cell disorder. We report the case of a 46-year old female patient with multicentric Castleman's disease and limb ischemia. Thrombotic occlusions of the popliteal and tibioperoneal arteries were treated by percutaneous thrombus aspiration. We discuss the role of increased interleukin-6 plasma levels during therapy with Tocilizumab, an antibody to interleukin-6 receptor, as a potential cause for arterial thrombosis.

Targeted deletion of the inhibitory NF-kappaB p50 subunit in bone marrow-derived cells improves collateral growth after arterial occlusion.

AIMS: Adaptive collateral artery growth (arteriogenesis) is an important mechanism to maintain tissue perfusion upon arterial obstruction. Leucocytes and inflammatory mediators play a crucial role in this process. Depletion of the nuclear factor kappa B (NF-κB) p50 subunit modulates inflammatory processes in cardiovascular disease. We hypothesized that NF-κB p50 is a regulator of the inflammatory response after arterial occlusion and subsequent collateral perfusion. METHODS AND RESULTS: Unilateral femoral artery ligation was performed in NF-κB p50-/- and wild-type (Wt, B6/129PF2) mice. Seven days after arterial occlusion, tissue perfusion restoration was significantly enhanced in NF-κB p50-/- mice compared with Wt mice (42.9 ± 3.9 vs. 32.0 ± 2.6% perfusion recovery, P = 0.04). Transplantation of NF-κB p50-/- bone marrow (bm) into Wt mice and vice versa showed that the effect of p50 subunit depletion can be predominantly attributed to the bone marrow-derived circulating cells (NF-κB p50-/- bm in Wt mice 42.1 ± 1.5%, Wt bm in NF-κB p50-/- mice 35.4±1.5% perfusion recovery). Histological analyses revealed a more elaborate extravasation of monocytes in hindlimb tissue of NF-κB p50-/- mice. Chemotaxis assays confirmed the increased migration ability of NF-κB p50-/- monocytes, which may be due to an observed increased integrin expression. Upon stimulation of blood from NF-κB p50-/- and Wt mice more interleukin-6 was produced, confirming the pro-inflammatory phenotype in absence of the p50 subunit. CONCLUSION: Depletion of the NF-κB p50 subunit enhances collateral artery growth. Its absence in circulating cells improves tissue perfusion restoration after femoral artery ligation by increasing macrophage influx into the growing collateral vessels.

Free flap failure in an anticardiolipin antibody-positive patient with neoplasm--a case report.

We present herein a case of massive arterial thrombosis of a free rectus abdominal musculocutaneous flap used for reconstructive surgery of gingival carcinoma that could not be rescued. A 54-year-old woman underwent the operation. She had experienced two miscarriages in her 20s, but medical history was otherwise uneventful. Intraoperatively, the anastomosed artery often showed massive arterial thrombosis, and the flaps had become necrotic after bilateral flaps were used. Laboratory findings, 7 days postoperatively, showed high levels of immunoglobulin G anticardiolipin antibody. This value normalized by 2 months postoperatively after using chemotherapy. This case does not match the criteria for antiphospholipid syndrome, but some English-language reports have shown rising antiphospholipid antibody levels, particularly anticardiolipin antibodies, in patients with neoplasm. In those cases, levels have normalized after successful therapy. Antiphospholipid antibody levels should be examined before surgery to identify risks of hypercoagulability.

Is obstetric antiphospholipid syndrome a primary nonthrombotic, proinflammatory, complement-mediated disorder related to antiphospholipid antibodies?

UNLABELLED: Pregnancy loss is the main obstetrical complication of the obstetric antiphospholipid syndrome. Classically, such losses have been attributed to placental thrombosis and infarcts, although in many cases there is no evidence of decidual thrombosis or placental vasculopathy, and instead inflammatory signs are present. In addition, the prevalence of systemic thrombosis is low in obstetric antiphospholipid syndrome, suggesting an alternative pathogenesis. There is evidence that antiphospholipid antibodies, mainly beta2-glycoprotein-I/anti-beta2-glycoproteina-I complexes, activate both classical and alternative complement pathways. Complement proteins may injure trophoblast cells, recruiting and activating monocytes and neutrophils. Free radicals and proteolytic enzymes could also attack trophoblastic cells, and amplification of the causal loop between tissue factor, inflammatory cells, and complement proteins could also be a factor. Overall, these diverse mechanisms may explain both inflammatory and thrombotic placental alterations. The role played by certain pro-inflammatory cytokines, mainly tumor necrosis factor-alpha, and the altered balance between angiogenic and anti-angiogenic factors remains to be clarified. In the end, obstetric antiphospholipid syndrome seems to be a clinical subset of classical APS. In these women, systemic thrombotic risk seems to be low. Current knowledge about inflammatory pathway involvement in obstetric antiphospholipid syndrome will permit us to modify the time to start heparin treatment, currently recommended to begin it as soon as possible after pregnancy confirmation. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader will be able to recall manifestations of obstetric antiphospholipid syndrome, describe nonthrombotic mechanisms that may affect obstetric outcomes in women with antiphospholipid syndrome, and predict changes in the evaluation and treatment of obstetric patients with antiphospholipid syndrome should inflammatory factors prove to be an important feature of antiphospholipid syndrome.

Deficiency of tumour necrosis factor-alpha and interferon-gamma in bone marrow cells synergistically inhibits neointimal formation following vascular injury.

AIMS: Neointimal formation after percutaneous coronary intervention (PCI), termed restenosis, limits therapeutic revascularization. Since it is now known that vascular injury involves an inflammatory response, we examined the role of tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in the neointimal formation after injury. METHODS AND RESULTS: Control (BALB/c), TNF-alpha-deficient (Tnf(-/-)), IFN-gamma-deficient (Ifng(-/-)), or double-deficient (Tnf(-/-)Ifng(-/-)) mice were subjected to wire-mediated vascular injury of the right femoral artery. Neointimal formation after injury was significantly reduced after the injury in the Tnf(-/-)Ifng(-/-) mice, compared to that in the control, Tnf(-/-), and Ifng(-/-) mice. Immunohistochemical analysis showed that TNF-alpha and IFN-gamma were expressed in neointimal lesions in the control mice, but not in mice with deficiency of the corresponding cytokine. No significant difference in re-endothelialization was observed among these groups. The number of proliferating cell nuclear antigen in the neointimal lesions was significantly decreased in the Tnf(-/-)Ifng(-/-) mice. Bone marrow transplantation experiments revealed that deficiency of TNF-alpha and IFN-gamma specifically in bone marrow cells significantly inhibited neointimal formation after vascular injury. CONCLUSION: The absence of TNF-alpha and IFN-gamma in bone marrow cells synergistically inhibits neointimal formation following vascular injury, and thus, may provide new insights into the mechanisms underlying restenosis after PCI.

Circulating endothelial progenitor cells decrease in patients after endarterectomy.

BACKGROUND: Endothelial progenitor cells (EPC) contribute to vascular regeneration. Since surgical injury and burns induce a pro-inflammatory and proangiogenic response, we investigated the effect of vascular injury with minimal surgical trauma after endarterectomy on the number of circulating EPC and systemic inflammatory changes. METHODS AND RESULTS: Forty-five patients with peripheral arterial occlusive disease were included in the study. Venous blood samples were taken before and 1 day after endarterectomy and plaque material was obtained. Ten patients with minor surgery served as controls. Circulating CD133+CD34+, VEGFR-2+CD34+ progenitor cells and surface expression of CD11b on circulating neutrophils were analysed using flow cytometry. EPCs were characterized in a culture assay as double-positive for DiI-LDL uptake and lectin binding. Cytokine concentrations of interleukin (IL)-6, IL-8, TNF-alpha, IL-1ss, IL-10, IL-12, SDF-1, G-CSF, and VEGF were measured in plasma and tissue samples. After endarterectomy a significant decrease in circulating EPC, CD133+CD34+, and VEGFR-2+CD34+ cells was observed. This was associated with a specific pattern of changes in circulating cytokine levels after endarterectomy with a decrease in IL-1 beta and IL-12, an increase in IL-6 and G-CSF plasma concentrations, and surface expression of CD11b on circulating neutrophils. In contrast, after minor surgery an increase in circulating CD133+CD34+ cells, IL-6, IL-8, and IL-10 was found. Interestingly there was a negative association between levels of local IL-6 within the plaque and only the preoperative levels of circulating CD133+C34+. CONCLUSION: Endarterectomy induces changes in circulating cytokines and a decline in circulating progenitor cells, which may be due to recruitment of progenitor cells to the injured vessels. This is supported by the negative association between plaque inflammation and circulating progenitor cells before endarterectomy.

The presence of anti-phosphatidylserine/prothrombin antibodies as risk factor for both arterial and venous thrombosis in patients with systemic lupus erythematosus.

In an effort to clarify the clinical significance of anti-phospholipid antibodies (aPL) detected by enzyme-linked immunosorbent assay (ELISA), we examined the prevalence of anti-cardiolipin antibodies (aCL), anti-beta2-glycoprotein I antibodies (anti-beta2-GPI), antiprothrombin antibodies (anti-PT), and anti-phosphatidylserine/prothrombin antibodies (anti-PS/PT) in 175 patients with systemic lupus erythematosus (SLE) comprising 67 patients with thrombotic complications. The present study showed that positive results of anti-beta2-GPI-ELISA and anti-PS/PT-ELISA could serve as markers of thrombotic complications in patients with SLE, whereas aCL and anti-PT are less reliable as markers of these complications. Furthermore, results of the anti-PS/PT-ELISA correlate best with the occurrence of both arterial and venous thrombosis in patients with SLE.

Cellular, molecular and immunological mechanisms in the pathophysiology of vein graft intimal hyperplasia.

Coronary artery disease, leading to myocardial infarction and ischaemia, affects millions of persons and is one of the leading causes of morbidity and mortality worldwide. Invasive techniques such as coronary artery bypass grafting are used to alleviate the sequelae of arterial occlusion. Unfortunately, restenosis or occlusion of the grafted conduit occurs over a time frame of months to years with a gradual reduction in patency, especially in vein grafts. The events leading to intimal hyperplasia (IH) formation involve numerous cellular and molecular components. Various cellular elements of the vessel wall are involved as are leucocyte-endothelial interactions that trigger the coagulation cascade leading to localized thrombus formation. Subsequent phenotypic modification of the medial smooth muscle cells and their intimal migration is the basis of the lesion formation that is thought to be propagated by an immune-mediated reaction. Despite intense scrutiny, the pathophysiology of IH remains an enigma. Although several growth factors, cytokines and numerous other biomolecules have been implicated and their relationship to prohyperplasia pathways such as the phosphatidyl-inositol 3-kinase (PI3K)-Akt pathway has been established, many pieces of the puzzle are still missing. An in-depth understanding of early vein graft adaptation and progression is necessary to improve the long-term prognosis and develop more effective therapeutic measures. In this review, we have critically evaluated and summarized the literature to elucidate and interlink the numerous established and emerging factors that play a key role in the development of IH leading to vein graft restenosis.

Evolution of spinal cord injury in a porcine model of prolonged aortic occlusion.

BACKGROUND: Spinal cord injury and subsequent paraplegia remains an unpredictable and devastating complication of thoracoabdominal aortic surgery. The aim of this study was to investigate spinal cord injury due to prolonged thoracoabdominal aortic occlusion. MATERIALS AND METHODS: We used a highly reproducible porcine model of 45-min thoracoabdominal aortic occlusion, which was accomplished by two balloon occlusion catheters. Neurological evaluation after the end of experiment was performed by an independent observer according to the Tarlov scale. The lower thoracic and lumbar spinal cords were harvested at 10, 48, and 120 h (n = 6 animals per time point) and examined histologically with hematoxylin and eosin (H&E) stain and TUNEL method. Tarlov scores, number of neurons, and the grade of inflammation were analyzed. RESULTS: H&E staining revealed reduction in the number of motor neurons which occurred in two phases (between 0 and 10 h and between 48 and 120 h of reperfusion), as well as development of inflammation in spinal cord sections during the reperfusion period, reaching a peak at 48 h. TUNEL reaction was negative for apoptotic neurons at any time point. CONCLUSIONS: In this porcine model, we demonstrated that, after 45 min of thoracoabdominal aortic occlusion, motor neuron death seems to occur in two phases (immediate and delayed). Inflammation was a subsequent event of transient prolonged spinal cord ischemia and possibly a major contributor of delayed neuronal death. Using TUNEL straining we found no evidence of neuronal apoptosis at any time point of reperfusion.

Anti-tumor necrosis factor-{alpha} therapies attenuate adaptive arteriogenesis in the rabbit.

The specific antagonists of tumor necrosis factor-alpha (TNF-alpha), infliximab and etanercept, are established therapeutic agents for inflammatory diseases such as rheumatoid arthritis and Crohn's disease. Although the importance of TNF-alpha in chronic inflammatory diseases is well established, little is known about its implications in the cardiovascular system. Because proliferation of arteriolar connections toward functional collateral arteries (arteriogenesis) is an inflammatory-like process, we tested in vivo the hypothesis that infliximab and etanercept have antiarteriogenic actions. Sixty-three New Zealand White rabbits underwent femoral artery occlusion and received infliximab, etanercept, or vehicle according to clinical dosage regimes. After 1 wk, collateral conductance, assessed with fluorescent microspheres, revealed significant inhibition of arteriogenesis (collateral conductance): 52.4 (SD 8.1), 35.2 (SD 7.7), and 33.3 (SD 10.1) ml x min(-1) x 100 mmHg(-1) with PBS, infliximab, and etanercept, respectively (P < 0.001). High-resolution angiography showed no significant differences in number of collateral arteries, but immunohistochemical analysis demonstrated a decrease in mean collateral diameter, proliferation of vascular smooth muscle cells, and reduction of leukocyte accumulation around collateral arteries in treated groups. Infliximab and etanercept bound to infiltrating leukocytes, which are important mediators of arteriogenesis. Infliximab induced monocyte apoptosis, and neither substance affected monocyte expression of the adhesion molecule Mac-1. We demonstrated that TNF-alpha serves as a pivotal modulator of arteriogenesis, which is attenuated by treatment with TNF-alpha inhibitors. Reduction of collateral conductance is most likely due to inhibition of perivascular leukocyte infiltration and subsequent lower vascular smooth muscle cell proliferation. This is the first report showing a negative influence of TNF-alpha inhibitors on collateral artery growth.

The effect of gradual or acute arterial occlusion on skeletal muscle blood flow, arteriogenesis, and inflammation in rat hindlimb ischemia.

BACKGROUND: Current experimental models of critical limb ischemia are based on acute ischemia rather than on chronic ischemia. Human peripheral vascular disease is largely a result of chromic ischemia. We hypothesized that a model of chronic hindlimb ischemia would develop more collateral arteries, more blood flow, and less necrosis and inflammation than would acute hindlimb ischemia. We therefore developed a rat model of chronic hindlimb ischemia and compared the effects of chronic ischemia with those of acute ischemia on hindlimb skeletal muscle. METHODS: Acute or chronic ischemia was induced in 36 male Sprague-Dawley rats. Chronic ischemia caused blood flow, as measured by laser Doppler scanning and confirmed by muscle oxygen tension measurements, to gradually decrease over 1 to 2 weeks after operation. RESULTS: Histologic analysis showed chronic hindlimb ischemia better preserved muscle mass and architecture and stimulated capillary angiogenesis, while lacking the muscle necrosis and inflammatory cell infiltrate seen after acute ischemia. Surprisingly, the chronic ischemia group recovered dermal blood flow more slowly and less completely than did the acute ischemia group, as measured by laser Doppler (0.66 +/- 0.02 vs 0.76 +/- 0.04, P < .05) and tissue oxygen tension (0.61 +/- 0.06 vs 0.81 +/- 0.05, P < .05) at 40 days postoperatively. Consistent with poorer blood flow recovery, chronic ischemia resulted in smaller diameter collateral arteries (average diameter of the five largest collaterals on angiogram was 0.01 +/- 0.0003 mm vs 0.013 +/- 0.0007 mm for acute, P < .005 at 40 days postoperatively). Acute ischemia resulted in decreased tissue concentrations of vascular endothelial growth factor (VEGF) (0.96 +/- 0.23 pg/mg of muscle for acute vs 4.4 +/- 0.75 and 4.8 +/- 0.75 pg/mg of muscle for unoperated and chronic, respectively, P < .05 acute vs unoperated), and in increased tissue concentrations of interleukin (IL)-1beta (7.3 +/- 4.0 pg/mg of muscle for acute vs undetectable and 1.7 +/- 1.6 pg/mg of muscle for unoperated and chronic, respectively, P < 0.05 acute vs unoperated). CONCLUSIONS: We describe here the first model of chronic hindlimb ischemia in the rat. Restoration of blood flow after induction of hindlimb ischemia is dependent on the rate of arterial occlusion. This difference in blood flow recovery correlates with distinct patterns of muscle necrosis, inflammatory cell infiltration, and cytokine induction in the ischemic muscle. Differences between models of acute and chronic hindlimb ischemia may have important consequences for future studies of mechanisms regulating arteriogenesis and for therapeutic approaches aimed at promoting arteriogenesis in humans suffering from critical limb ischemia. CLINICAL RELEVANCE: Despite the substantial clinical differences between acute and chronic ischemia, researchers attempting to develop molecular therapies to treat critical limb ischemia have only tested those therapies in experimental models of acute hindlimb ischemia. We present here a novel model of chronic hindlimb ischemia in the rat. We further demonstrate that when hindlimb ischemia is developed chronically, collateral artery development is poorer than when hindlimb ischemia is developed acutely. These findings suggest that further tests of molecular therapies for critical limb ischemia should be performed in chronic hindlimb ischemia models rather than in acute hindlimb ischemia models.

Risk of treatment of peripheral arterial disease is related to inflammation-sensitive plasma proteins: a prospective cohort study.

BACKGROUND: Studies in patients with peripheral arterial disease (PAD) have reported an association between inflammatory markers and severity of disease or worsening of symptoms. However, few have studied the prognostic significance of inflammatory markers in asymptomatic subjects, measured many years before the onset of symptomatic PAD requiring treatment (trPAD). MATERIAL AND METHODS: Five inflammation-sensitive plasma proteins (ISPs), including fibrinogen, alpha 1-antitrypsin, haptoglobin, ceruloplasmin, and orosomucoid, were determined in 5619 healthy men (mean age, 46.8 +/- 3.7 years) without walking-induced calf pain. Data for men who subsequently underwent a revascularization procedure because of trPAD (intermittent claudication or critical ischemia) were retrieved from hospital-based registers. Future trPAD was studied in relation to the number of ISPs in the top quartile at the baseline examination. RESULTS: Seventy men (1.2%) underwent revascularization because of trPAD at a mean of 16.5 years after the baseline examination. The proportion with future trPAD was 0.4%, 1.0%, 1.5%, and 3.2%, respectively, for men with 0, 1, 2, and 3 or more ISPs in the top quartile (trend, P < .0001). After adjustment for age, screening year, systolic blood pressure, blood pressure medication, cholesterol concentration, diabetes, smoking, and tobacco consumption the corresponding odds ratios (95% confidence interval [CI]) were 1.00 (reference), 1.5 (CI, 0.7-3.6), 1.9 (CI, 0.8-4.6), and 2.9 (CI, 1.3-6.4), respectively, in these groups (trend, P = .003). CONCLUSION: Elevated ISPs, measured 16 years earlier in apparently healthy men without walking-induced calf pain, were associated with increased risk for development of PAD requiring revascularization.

[Relationship between the peripheral arterial occlusive disease and the infection by Chlamydophila pneumoniae]. / Relación entre la enfermedad arterial periférica oclusiva y la infección por Chlamydophila pneumoniae.

BACKGROUND AND OBJECTIVE: The relationship between peripheral arterial occlusive disease (PAOD) and Chlamydophila pneumoniae infection was studied by analyzing clinical samples from 95 patients with PAOD (cases) and 100 controls. PATIENTS AND METHOD: The following investigations were conducted: IgG and IgA against lipopolysaccharide (LPS) and against purified C. pneumoniae-specific antigens from elementary bodies (EB) with ELISA; anti-EB IgG, with MIF; C. pneumoniae DNA in arterial biopsy and peripheral blood leukocyte cells (PBLCs) with heminested PCR; LPS with ELISA; and bacteria culture in HEp-2 cells from arterial biopsy. RESULTS: The percentage of positive results in cases and controls groups for anti-LPS IgG was: 21% and 14%, respectively, with no differences; nor were there any differences with IgA (22 and 21%, respectively). However, differences were seen in the anti-EB IgG between cases (74% and 72%, for ELISA and MIF, respectively) and controls (31% and 34%). There were no differences in anti-EB IgA. Bacterial DNA was detected in 67% of atheromatous plaques (cases) vs. 12% of pudendal arteries (controls) (p = 0.0001). No C. pneumoniae DNA and LPS was detected in PBLCs and biopsic samples, respectively; and no C. pneumoniae strain could be recovered by cell culture from cases. CONCLUSIONS: On the basis of our results, PAOD is significantly associated with C. pneumoniae infection through the detection of anti-EB IgG from serum and bacterial DNA from arterial biopsy.

Genomic, serologic, and clinical case-control study of Chlamydia pneumoniae and peripheral artery occlusive disease.

OBJECTIVES: Chlamydia pneumoniae has been related to atherosclerotic disease in both seroepidemiologic and genomic studies. We performed a case-control study to determine seropositivity and DNA detection in arteries of patients with peripheral artery occlusive disease and of healthy subjects. METHODS: The study included 64 patients with peripheral artery occlusive disease, and 50 control subjects who underwent varicose vein surgery, matched to the patient group for age, sex, and tobacco use. The fibrinogen level in all study subjects was measured as a marker of inflammation. Blood samples were taken from all subjects for determination of immunoglobulin (Ig) G elementary bodies (EB) against C pneumoniae with microimmunofluorescence (MIF) and enzyme-linked immunosorbent assay (ELISA), and of IgA EB with ELISA. The cutoff titers were 1:32 for MIF and 1.1 for ELISA. Biopsy specimens of arterial atheromatous plaque were obtained from patients, and of pudendal artery and saphenous vein from control subjects, and were studied with hemi-nested polymerase chain reaction. RESULTS: There were no differences in fibrinogen level between patients and controls. The prevalence of IgG anti-EB with MIF was 78% in patients and 24% in control subjects (P =.0001; odds ratio [OR], 11.3; 95% confidence interval [CI], 4.7-27.2). Prevalence of IgG anti-EB with ELISA was 75% in patients and 16% in control subjects (P =.0001; OR, 15.7; 95% CI, 6.1-40). There were no differences in IgA anti-EB titers. Bacterial DNA was detected in 67% of atheromatous plaques versus 12% of pudendal arteries (P =.0001) and 4% of saphenous veins. A weak correlation was found between seropositivity and the presence of intravascular DNA. CONCLUSIONS: Our results support the hypothesis that C pneumoniae is related to the pathogenesis of atherosclerotic peripheral artery occlusive disease. CLINICAL RELEVANCE: This study explored the infectious hypothesis in the context of the pathogenesis of atherosclerosis. This hypothesis has been supported by findings that certain infectious agents can cause or accelerate the course of diseases in which the possibility of a microbial cause was not previously proposed, as in the case of peptic ulcer and spongiform encephalopathy. The present study demonstrated the presence of Chlamydia pneumoniae and seropositivity in atheromatous plaques in patients with peripheral artery occlusive disease. These results contribute to a body of research that is opening up the possibility of treating atherosclerotic disease with antibiotic agents, and preventing it with immunization.

Myocyte enhancer factor 2 mediates vascular inflammation via the p38-dependent pathway.

Although it has been established that myocyte enhancer factor 2 (MEF2) plays pivotal roles in the development of the cardiovascular system as well as skeletal muscle cells, little is known of its role in vascular inflammatory diseases such as atherosclerosis and restenosis after angioplasty. To investigate the role of MEF2 in vascular inflammation and that of p38 in the activation of MEF2, we infected cultured rat vascular smooth muscle cells (VSMCs) with an adenovirus construct expressing a dominant-negative mutant of MEF2A (MEF2ASA) or mitogen-activated protein kinase kinase 6 (MEK6AA), and examined their effects on the expression of monocyte chemoattractant protein-1 (MCP-1), which is known to play important roles in vascular inflammation. We also examined the role of MEF2 in vivo using a rat model of transluminal wire-induced injury of the femoral artery. Angiotensin II (Ang II)-induced expression of MCP-1 mRNA was significantly inhibited by infection with adenoviruses encoding MEF2ASA (AdMEF2ASA) or MEK6AA. Ang II-induced increase of MCP-1 promoter activity was also significantly suppressed by overexpression of MEF2ASA or MEK6AA. Ang II stimulated the transactivating function of MEF2A and this activation was inhibited by overexpression of MEK6AA. Infection with AdMEF2ASA suppressed MCP-1 expression in the femoral artery after the transluminal mechanical injury. AdMEF2ASA infection also inhibited macrophages infiltration and neointimal formation in the wire-injured femoral arteries. These results suggested that MEF2 activation via the p38-dependent pathway mediates vascular inflammation via stimulation of MCP-1 expression in VSMCs and macrophages infiltration.

Wegener's granulomatosis.

Wegener's granulomatosis is an organ- and/or life-threatening autoimmune disease of as yet unknown etiology. The classic clinical triad consists of necrotizing granulomatous inflammation of the upper and/or lower respiratory tract, necrotizing glomerulonephritis, and an autoimmune necrotizing systemic vasculitis affecting predominantly small vessels. The detection of antineutrophil cytoplasmic antibodies directed against proteinase 3 (PR3-ANCA) is highly specific for Wegener's granulomatosis. ANCA positivity is found only in about 50% of the patients with localized Wegener's granulomatosis (which is restricted to the respiratory tract and affects < or = 5% of the patients), whereas PR3-ANCA positivity is seen in 95% of the patients with generalized Wegener's granulomatosis. Studies showing an expansion of circulating tumor necrosis factor-(TNF-)alpha-producing Th1-type CD4(+)CD28(-) T-cell effector memory T-cells and their presence as Th1-type cytokine profile- driving cell population within granulomatous lesions provide the rationale for using TNF-alpha-blocking agents in Wegener's granulomatosis refractory to standard induction therapy with cyclophosphamide and corticosteroids ("Fauci's scheme"). Vasculitis is an independent risk factor for diffuse endothelial dysfunction and may be a consequence of TNF-alpha action on endothelial cells. Recently, another study has shown intima-media thickening of the wall of the common carotid artery and bulb, as well as a significantly increased incidence of stroke, myocardial infarction and occlusive artery disease in Wegener's granulomatosis. This study suggests that systemic inflammation and vasculitis contribute to accelerated arteriosclerosis in Wegener's granulomatosis.