Raffaella Coppola

Tissue-factor antigen and activity in human coronary atherosclerotic plaques.

BACKGROUND Coronary atherosclerotic-plaque thrombosis is a key event in the pathogenesis of unstable angina and myocardial infarction. Although plaque rupture or fissuring frequently occurs in atherosclerosis, only a small proportion of ruptured plaques develop thromboses. METHODS Tissue-factor antigen and activity were measured in atherectomy samples from 50 consecutive patients with coronary artery disease (stable angina n = 19, unstable angina n = 24, and myocardial infarction n = 7). FINDINGS Median tissue-factor antigen and activity concentrations were significantly higher in plaques from patients with unstable angina and myocardial infarction than in those from patients with stable angina (antigen: 66.1 pg/mg [interquartile range 43.8-82.5] vs 32.4 pg/mg [9.8-43.4], p = 0.0001; activity: 0.22 mU/mg [0.17-0.41] vs 0.13 mU/mg [0.05-0.16], p = 0.0004). INTERPRETATION Tissue-factor, an initiator of the coagulation cascade, may account for the different thrombotic responses to the rupture of human coronary atherosclerotic plaques.

Hemostasis factors and aging

With advancing age, an increasing number of healthy individuals have laboratory signs of heightened coagulation enzyme activity. Such biochemical hypercoagulability might be the basis of either the increased thrombotic tendency occurring with age or a harmless manifestation of this process. Centenarians had striking signs of heightened coagulation enzyme activity, accompanied by signs of enhanced formation of fibrin and secondary hyperfibrinolysis. Plasma concentrations of fibrinogen and factor VIII were higher than in controls, whereas other coagulation factors were not elevated. It is of interest that centenarians have a significantly higher frequency than young individuals of the high risk 4G allele of the PAI-1-675 (4G/5G) polymorphism, mutant factor V (Arg506Gln) and prothrombin gene G20210A mutation. Von Willebrand factor (VWF), a well-known independent predictor of atherothrombotic disease, was increased in centenarians, independently of the blood group, confirming the previous results of a state of hypercoagulability. The finding that the VWF cleaving proteases levels are low when VWF levels are high in centenarians could be a corollary of the previous described paradox of successful aging, adding another marker of increased risk of atherothrombosis to the scenario. Alike, high prevalence of anti-phospholipids antibodies, not associated with an anti-phospholipid syndrome has been described in centenarians. In conclusion, the data show the oldest old do not escape the state of hypercoagulability associated with aging, but that this phenomenon is compatible with health and longevity. Hence, high plasma levels of the coagulation activation markers in older populations do not necessarily mirror a high risk of arterial or venous thrombosis.

Alterations of Factor VIII von Willebrand Factor in Clinical Conditions Associated with an Increase in its Plasma Concentration

Summary. Factor VIII‐related antigen (VIIIR: Ag) was consistently higher than factor‐VIII procoagulant activity (VIII:C) in 57 patients with clinical conditions characterized by acute‐phase reactions. Two different methods for measuring VIII:C (one‐ and two‐stage assays) and VIIIR: Ag (electroimmunodiffusion and immunoradiometric assay) gave concordant results in the majority of cases. In 43% of plasma samples, crossed immunoelectrophoresis in agarose gel was characterized by the appearance of an additional, fast‐moving precipitin peak which was immunologically identical with the major, slower‐moving VIIIR : Ag peak. The fast‐moving peak was detected in all the patients with clinical conditions typically associated with increased plasma proteolysis (DIC, acute pancreatitis, during thrombolytic therapy). It was present in a smaller proportion of cases with liver and renal failure and malignancies and in the post‐operative period. The additional VIIIR : Ag peak is thought to be the result of in vivo factor VIII/von Willebrand factor fragmentation by proteolytic enzymes.

Haemostatic and inflammatory biomarkers in advanced chronic heart failure: role of oral anticoagulants and successful heart transplantation

Advanced chronic heart failure (CHF) is associated with abnormal haemostasis and inflammation, but it is not known how these abnormalities are related, whether they are modified by oral anticoagulants (OAT), or if they persist after successful heart transplantation. We studied 25 patients with CHF (New York Heart Association class IV, 10 of whom underwent heart transplantation) and 25 age‐ and sex‐matched healthy controls by measuring their plasma levels of prothrombin fragment 1 + 2 (F1 + 2), thrombin–antithrombin (TAT) complexes, tissue plasminogen activator (t‐PA), plasminogen activator inhibitor‐1 (PAI‐1), D‐dimer, factor VII (FVII), fibrinogen, von Willebrand factor (VWF), tumour necrosis factor (TNF), soluble TNF receptor II (sTNFRII), interleukin 6 (IL‐6), soluble intercellular adhesion molecule‐1 (sICAM‐1), soluble vascular cell adhesion molecule‐1 (sVCAM‐1), endothelial‐selectin (E‐selectin) and thrombomodulin. CHF patients had higher plasma levels of TAT, D‐dimer, t‐PA, fibrinogen, VWF, TNF, IL‐6, sTNFRII, sVCAM‐1 (P = 0·0001), sICAM‐1 (P = 0·003) and thrombomodulin (P = 0·007) than controls. There were significant correlations (r = 0·414–0·595) between coagulation, fibrinolysis, endothelial dysfunction and inflammation parameters, which were lower in those patients treated with OATs. Heart transplantation led to reductions in fibrinogen (P = 0·001), VWF (P = 0·05), D‐dimer (P = 0·05) and IL‐6 levels (P = 0·05), but all the parameters remained significantly higher (P = 0·01–0·0001) than in the controls. Advanced CHF is associated with coagulation activation, endothelial dysfunction and increased proinflammatory cytokine levels. Most of these abnormalities parallel each other, tend to normalize in patients treated with OATs and, although reduced, persist in patients undergoing successful heart transplantation, despite the absence of clinical signs of CHF.

Activation of factor XII and cleavage of high molecular weight kininogen during acute attacks in hereditary and acquired Cl-inhibitor deficiencies

Hereditary and acquired C1-inhibitor (C1-INH) deficiencies (hereditary angioedema, HAE and acquired angioedema, AAE) are characterized by episodic increases in vasopermeability due to kinin release. Despite continuously defective C1-INH levels, symptoms only recur occasionally suggesting an episodic generation of pathogenetic factors induced by activation of the protease systems regulated by C1-INH. We evaluated activation of factor XII by measuring plasma levels of FXIIa with a commercial ELISA and cleavage of high molecular weight kininogen by performing SDS PAGE and immunoblotting analysis during 5 attacks in 5 different patients with HAE and during 7 attacks in 3 patients with AAE. The patients were also studied during remission. We confirmed our previous data indicating that during attacks both HAE and AAE patients had very high levels of cleaved HK (p < 0.0001) whereas during remission cleaved HK levels were normal in HAE and significantly increased in AAE (p < 0.0001). Both in HAE and in AAE, plasma levels of FXIIa were normal during remission and significantly increased during acute attacks (p = 0.0126; p = 0.0003). Our data suggest that the activation of a contact system is required to produce clinical symptoms.

Heightened Thrombin Formation but Normal Plasma Levels of Activated Factor VII in Patients With Acute Coronary Syndromes

Plaque rupture with the exposure of a tissue factor-rich procoagulant surface is considered the common pathogenetic mechanism of unstable angina and myocardial infarction. Activated factor VII, the key enzyme for initiating blood coagulation under resting conditions, is increased in pathological situations associated with tissue factor exposure. We measured the plasma levels of activated factor VII and studied their relation with signs of coagulation enzyme activity in patients with acute coronary syndromes. The plasma levels of activated factor VII, prothrombin fragment 1 + 2, and fibrinopeptide A were measured on admission in consecutive patients presenting with acute myocardial infarction (n = 28), unstable angina (n = 32), and stable angina (n = 17) and in age- and sex-matched healthy individuals (n = 33). Plasma determinations of the same markers were also repeated at 15 days and 3 and 6 months. On admission, the patients with unstable angina or myocardial infarction had significantly higher plasma levels of prothrombin fragment 1 + 2 (P < .0001) and fibrinopeptide A (P < .0001) than those with stable angina or healthy individuals, whereas no differences were detected in the plasma levels of activated factor VII. During follow-up there was a significant decrease in the plasma levels of fibrinopeptide A both in patients with unstable angina (P < .001) and in those with myocardial infarction (P < .001), whereas no changes in plasma prothrombin fragment 1 + 2 or activated factor VII levels were observed. Hence, in the acute and chronic phases of myocardial infarction and unstable angina, heightened coagulation enzyme activity is not accompanied by an increase in activated factor VII.

Measurement of activated factor XII in health and disease.

We investigated a new ELISA for measuring activated factor XII (FXIIa) in plasma. The intra-assay coefficient of variation was 3.5% and 5.1% for plasma containing 2.5 and 8.2 ng/ml FXIIa. The inter-assay coefficient of variation was 6.2% and 6.6%. FXIIa correlated with age in women older than 55 years (r = 0.55, P = 0.0003). Mean levels in the whole population of 160 healthy individuals included in this study were not different between men and women, but women younger than 55 years had lower levels than older women and men of the corresponding age. In a group of 25 healthy centenarians FXIIa was significantly higher (3.2 ng/ ml, 95% CI 2.3-3.6) than in controls (2.1 ng/ml, 95% CI 1.8-2.4). Increased levels were also found in pregnancy, with higher levels in the third trimester (4.7 ng/ml, 95% CI 3.9-5.5) than in the first trimester (2.9 ng/ml, 95% CI 2.2-3.9). FXIIa was unmeasurable in patients with FXII deficiency, but normal in patients with FXI deficiency and C1-inhibitor deficiency. FXIIa was significantly higher than in normal controls in patients with severe sepsis (3.9 ng/ml, 95% CI 2.8-5.4) and septic shock (5.4 ng/ml, 95% CI 3.7-7.7). After treatment with thrombolytic agents, a marked increase of FXIIa was found in patients with myocardial infarction. In conclusion, the immunoassay of FXIIa permits to study more directly the contact phase of blood coagulation in situations in which the involvement of this system may play a pathophysiological role.

VASCULAR DEMENTIA ITALIAN SULODEXIDE STUDY (VA.D.I.S.S.) CLINICAL AND BIOLOGICAL RESULTS.

In order to evaluate the biological effects on some haemostasis factors of antithrombotic-hemorheological treatments on patients with vascular dementia, a multicenter, randomized, double-blind, double-dummy, study comparing sulodexide (Sdx, 50 mg bid orally for 6 months) and pentoxifylline (Ptx, 400 mg tid orally for six months) was carried out. Eighty-six patients, 46 in Sdx group, 40 in Ptx group, fulfilling the NINDS-AIREN criteria for probable vascular dementia were evaluated. Plasma fibrinogen levels showed a significant reduction in both groups, in patients with high basal levels (> or = 350 mg/dl), the reduction being earlier in Sdx group (2nd month of therapy) than in Ptx group (4th month of therapy). In Sdx group a significant reduction in factor VII-Ag (baseline 102.8 U/dl; 6th month 90.1 U/dl) was also observed. Both drugs induced a slight reduction in activated factor VII levels as well. A parallel improvement of G.B.S. Rating Scale for dementia scores was observed in Sdx group. These results seem to indicate that sulodexide treatment can have positive effects in vascular dementia.

The increase with age of the components of the tissue factor coagulation pathway is gender-dependent

To evaluate the influence of age and gender on the components of the tissue factor coagulation pathway, plasma levels of tissue factor pathway inhibitor (TFPI), activated factor VII (FVIIa) and factor VII coagulant activity (FVIIc) were measured in 160 normal individuals. The female (n = 82) and male (n = 78) part of the population were matched for age, which was equally distributed from 21 to 101 years. Mean levels of TFPI were lower and those of FVIIc higher in women than in men; there was no gender-related difference for FVIIa. Linear regression analysis showed a positive correlation between age and TFPI (r = 0.34, P = 0.0001), FVIIa (r = 0.36, P = 0.0001) and FVIIc (r = 0.40, P = 0.0001). For each measurement, the positive correlation with age was mainly contributed by the female part of the population (TFPI: r = 0.51, P = 0.0001; FVIIa: r = 0.47, P = 0.0001; FVIIc: r = 0.58, P = 0.0001), whereas there was no significant correlation between age and TFPI, FVIIa or FVIIc in males. The gender-related difference of the association of these measurements with age was confirmed by comparing men or women older than 55 years with those younger than 55 years. TFPI, FVIIa and FVIIc were much higher in the older women group (P < 0.0002), whereas in the male part of the population only FVIIc was slightly higher in the older group (P = 0.03). These results indicate that the increase with age of the components of the tissue factor pathway of blood coagulation is mainly contributed by the female part of the normal population.

Anti-beta 2 glycoprotein I antibodies in centenarians

BACKGROUND Non-organ-specific autoantibodies are present in centenarians without evidence of autoimmune diseases but conflicting or no data on anti-phospholipid and anti-phospholipid binding proteins were reported. OBJECTIVE To investigate the presence and antigen specificity of anti-phospholipid and anti-phospholipid binding proteins in centenarians. METHODS Seventy-seven centenarians, 70 adult controls, 65 unselected elderly subjects, and 38 old SENIEUR volunteers were investigated. Anti-cardiolipin, anti-human beta 2 glycoprotein I, and lupus anticoagulant were detected. Antigen specificity was assayed against plates coated with anionic, neutral and cationic phospholipids and beta 2 glycoprotein I-dependence was also evaluated. RESULTS 54.3% of the centenarians were positive for IgG and 8.6% for IgM anti-beta 2 glycoprotein I antibodies, while only 20.7% centenarians were positive for anti-cardiolipin IgG and 2.59% for IgM; none resulted positive for lupus anticoagulant. Anti-cardiolipin positive sera cross-reacted with negatively charged phospholipids and displayed decreased binding to serum-free cardiolipin-coated plates that was restored by human beta 2 glycoprotein I or fetal calf serum. CONCLUSIONS Centenarians display high reactivity against human beta 2 glycoprotein I but low binding to the bovine molecule in the anti-cardiolipin assay. In spite of the presence of antibodies comparable to those found in patients with the anti-phospholipid syndrome, no vascular events were reported suggesting the presence of unknown protective factors and/or the lack of triggering factors.