Ozcebe Oi

Impaired haemostatic kinetics and endothelial function in Behçet's disease

Objectives. This study was planned to explore the alterations of endothelial functions in the prethrombotic state of Behçets disease (BD) patients.

Selectin adhesion molecules in Behçet's disease

OBJECTIVES The pathogenesis of Behçets disease (BD) is closely related to endothelial cells, leucocyte functions and autoimmunity. The aim of this study was to investigate circulating selectin adhesion molecules, which are known to play a significant part in the immune response especially by regulating interactions of the leucocytes with endothelium, in BD. METHODS Plasma E-, L-, and P-selectin concentrations were evaluated in 11 patients with widespread BD (group I), 10 cases with merely mucocutaneous involvement (group II) and 15 age and sex matched healthy control subjects. The patients were newly or previously diagnosed cases not taking any drug for BD. RESULTS Plasma concentrations of all selectins were significantly higher in group I compared with group II. E-selectin and P-selectin were significantly increased in each subgroup of patients compared with the healthy controls. L-selectin concentrations were higher than the controls only in group I. CONCLUSIONS Increases in the selectins in BD may be a direct consequence of the leucocyte, endothelium and platelet activations observed during the disease process. However, abnormal/increased selectin expression to various triggers should also be considered. More prominent increases in patients with extensive disease suggest that circulating selectin concentrations are related to disease severity.

Effects of interferon-α2a treatment on serum levels of tumor necrosis factor-α, tumor necrosis factor-α2 receptor, interleukin-2, interleukin-2 receptor, and E-selectin in Behçet's disease

Abstract This study was performed to investigate serum levels of various cytokines and E-selectin in patients with Behçets disease (BD) before and after treatment with interferon-α2a (IFN-α). The study population consisted of 22 patients with active BD; 15 age- and sex-matched healthy adults served as the control group. IFN-α (3 million units subcutaneously) was given to all patients twice a week for 3 months. Twenty of twenty-two patients experienced clinical improvement with this therapy. Pre- and post-treatment serum levels of tumor necrosis factor-α (TNF-α), TNF-α2-receptor (TNFα2R), interleukin-2 (IL-2), IL-2 receptor (IL-2R), and E-selectin were measured by sandwich-type enzyme immunoassay. Baseline E-selectin, TNF-α, and TNF-α2R levels of the patients were increased in comparison with the control group and post-treatment values. However, IL-2 and IL-2R levels did not change either with treatment or compared with the control group levels. In conclusion, these results confirm the previously described efficacy of IFN-α in the treatment of BD. Serum levels of TNF-α, TNF-α2R, and E-selectin are prominently increased during active stage of the disease, indicating presence of immune system activation and endothelial injury/activation. Improvement of the pathological cytokinemia and endothelial disturbance accompany interferon-α-induced disease remission.

Megakaryocyte-Related Interleukins in Reactive Thrombocytosis versus Autonomous Thrombocythemia

The primary thrombocytosis (thrombocythemia) associated with myeloproliferative disorders is believed to be due to autonomous platelet production. Secondary or reactive thrombocytosis can be observed in a number of clinical circumstances, and may be related to persistent overproduction of some thrombocytopoietic factors acting on megakaryocytes. Several cytokines, including IL-6, IL-1 and IL-4 have been shown to act alone or in concert, to affect various cellular stages of megakaryocytopoiesis in humans. The aim of this study is to assess the serum concentrations of these cytokines in myeloproliferative disorders (MPD) with thrombocythemia and in rheumatoid arthritis (RA) with marked reactive thrombocytosis. Twenty-two patients (14 men, 8 women) with MPD and thrombocythemia (platelet counts > 500 x 10(9)/1; range 507-996 x 10(9)/1), 33 RA patients (28 women, 5 men) with marked thrombocytosis (platelet counts > 500 x 10(9)/1; range 500-745 x 10(9)/ 1), 27 RA patients (24 women, 3 men) with normal platelet counts (range 168-399 x 10(9)/1) and 15 healthy volunteers (8 women, 7 men) with normal platelet counts (range 161-385 x 10(9)/1) enrolled in the study. Serum IL-1 alpha, IL-1 beta, IL-4 and IL-6 concentrations were measured in these four groups. Of the 22 patients with MPD, 10 had chronic myelogenous leukemia, 5 had polycythemia vera, 6 had essential thrombocytosis and 1 had osteomyelofibrosis. Serum interleukin concentrations in patients with MPD and thrombocythemia were either suppressed or similar to those of normal subjects, whereas IL-6, IL-1 beta and IL-4 levels were increased in RA patients with reactive thrombocytosis. We conclude that thrombocythemia associated with MPD is an autonomous phenomenon, and is not regulated by cytokines which affect megakaryocytopoiesis.

Rational use of the PFA-100 device for screening of platelet function disorders and von Willebrand disease.

Two hundred and five patients referred for evaluation of platelet functions and 126 healthy controls were tested with the PFA-100 instrument. A cut-off value of 150 s for collagen/epinephrine (CEPI) closure time (CT) produced most acceptable sensitivity (90%), specificity (85.2%), and positive (82.6%) and negative (91.6%) predictivity values for screening of platelet function disorders and von Willebrand disease (vWD). All patients with vWD and Glanzmann thrombasthenia could be detected by PFA-100. Both CEPI and collagen/adenosine diphosphate (CADP) CTs were elevated in all of these cases. Sensitivity of the device was 81.6% for patients with platelet secretion defects. CADP CT was normal in 63.9% of the patients in this subgroup. Specificity (47%) and positive predictivity (57%) of the instrument were diminished in patients with low hemoglobin concentrations. Depending on the results, an algorithm was developed for screening of platelet function disorders and vWD with PFA-100.

Serum L-selectin and P-selectin levels in lymphomas.

The migration of normal and malignant lymphoid cells is governed by specific adhesion molecules. Selectins comprise a family of adhesion receptors expressed by leukocytes, platelets and endothelial cells. In this study, the serum levels of soluble L-selectin and P-selectin were measured in patients with non-Hodgkins lymphoma and Hodgkins disease and found to be significantly elevated in both patient groups compared to healthy controls. This result provides evidence that alterations in the expression and function of adhesion molecules may play an important role in the progression of lymphomas. Further studies are awaited to establish the exact roles of these adhesion molecules in distinct patterns of growth and spread of lymphomas.

Evaluation of the Haemostatic System during Ketoacidotic Deterioration of Diabetes mellitus

Clinical observations have indicated the frequent development of thrombotic complications during diabetic ketoacidosis (DKA). This study aimed to examine whether haemostatic changes that could lead to a thrombotic tendency occur during ketoacidosis. Plasma levels of in vivo haemostatic markers reflecting activation degrees of the coagulation system, fibrinolytic system, platelets and endothelium were assayed in 34 patients with DKA, both at diagnosis and 1 week after recovery. We found coagulation system and platelet activation and endothelial injury/activation in the patients at diagnosis of DKA. Although significant improvements were observed after recovery, only platelet activity was completely normalized. Fibrinolytic activity was also increased, both at diagnosis and after recovery, compared to the control group. However, although coagulation activity was prominently increased at diagnosis compared to the recovery period, there was no change in fibrinolytic activity in the same periods; on the contrary, the fibrinolytic capacity of the endothelium was diminished at diagnosis of DKA compared to the recovery period, suggesting the presence of relative hypofibrinolysis during DKA. Indications for a role of hyperglycaemia in the emergence of haemostatic disturbances during DKA were observed.

Increased erythrocyte aggregation as an indicator for an aggressive clinical course in Behçet’s disease: a prospective study

OBJECTIVE Changes in blood rheology, especially increased erythrocyte aggregation (EA) might play an important part in the development of arterial and venous thrombotic lesions. A prospective study was designed to evaluate EA in patients with Behçet’s disease (BD) and to see if this parameter is predictive for the future development of vascular complications, such as deep vein thrombosis of various organ systems and uveitis. METHODS EA was measured by a photometric Myrenne aggregometer in 38 patients with BD at the time of initial diagnosis and in 40 age and sex matched healthy controls (HC). RESULTS During a median follow up period of 13.5 months, 13 patients developed vascular-ocular complications (eight deep vein thrombosis, nine uveitis, and four both deep vein thrombosis and uveitis). Patients were further divided into two groups: BD-a with mucocutaneous symptoms and arthritis only; BD-b with associated vascular-ocular complications. EA values at high shear rate (M) and at low shear rate (M1) were compared among the groups. CONCLUSION EA values at M and M1 were significantly higher in BD-b than BD-a and HC (p<0.001). These results suggest that determination of EA rates might be useful to identify subgroups who are likely candidates for developing vascular-ocular complications in BD and management of factors known to affect blood rheology might be beneficial.

In vivo platelet and T-lymphocyte activities during pulmonary tuberculosis

Platelets have been suggested to play a role in the inflammatory response, including defence against bacteria. The aims of this study were to determine in vivo platelet activity during the clinical course of pulmonary tuberculosis and to investigate whether or not there is a correlation between the magnitude of platelet activation and the extent of the pulmonary disease. T-lymphocyte activity was also analysed in the patients. Platelet factor-4 (PF4) and soluble interleukin-2 receptor-alpha (sIL-2Ralpha) concentrations were used as markers of platelet and T-lymphocyte activation, respectively. Twenty-five patients with pulmonary tuberculosis were studied. Fifteen healthy subjects served as a control group. The levels of both sIL-2Ralpha (3,000+/-1,948 pg x mL(-1)) and PF4 (103.1+/-6.7 IU x mL(-1)) were significantly higher in the patients with tuberculosis than in the control group (984+/-360 pg x mL(-1) and 78.2+/-23.9 IU x mL(-1), respectively) (Mann-Whitney U-test, p<0.001 for both comparisons). The plasma PF4 levels were found to be well correlated with the extent of pulmonary lesions on chest radiography (the Spearmans bivariate correlation analysis, r=0.65, p<0.001). However, sIL-2Ralpha concentrations did not correlate with the extent of disease. In conclusion, it has been suggested that platelet and T-lymphocyte activation occurs during pulmonary tuberculosis. The good correlation between platelet activation and the extent of pulmonary tuberculosis might be ascribed to a pathophysiological role of platelets in pulmonary tuberculosis.

Enhanced expression of the local haematopoietic bone marrow renin-angiotensin system in polycythemia rubra vera

Local bone marrow (BM) renin-angiotensin system (RAS) affects physiological and pathological haematopoiesis, including erythropoiesis. In this study, quantitative expression of the messenger RNAs of the major RAS components – angiotensin-converting enzyme (CD143), renin and angiotensinogen – were measured in BM samples by quantitative real-time polymerase chain reaction, to evaluate the activity of local BM RAS in polycythemia rubra vera (PV) in comparison with normal erythropoiesis. The presence of CD143 was also investigated in the same BM samples by flow cytometry. Increased local synthesis of the major RAS components has been identified by demonstrating corresponding mRNAs in the BM of the patients with PV. Our findings indicate up-regulation of local BM RAS, together with down-regulation of the cell surface angiotensin-converting enzyme receptors, in the autonomous neoplastic clonal erythropoiesis of PV.