Iwona Prajs

Endothelial progenitor cells and left ventricle function in patients with acute myocardial infarction: potential therapeutic considertions.

Endothelial progenitor cells (EPCs) play a key role in angiogenesis and vascular repair, although their exact functions are still disputable. The impact of EPC on left ventricular ejection fraction (LVEF) during acute myocardial infarction (MI) in patients treated with primary percutaneous coronary intervention (PCI) is also under investigation. The aim of this study was to assess the impact of different populations of EPC on LVEF during and 6 months after acute MI treated with primary PCI. The study included 34 patients with documented acute anterior wall MI. The control group consisted of 19 apparently healthy subjects. Blood for EPC assessments was obtained during the first 24 hours after MI and at 7 days and 6 months after PCI. CD34+/CD133+/CD45−, CD34+/CD31+/CD45−, CD34+/CD105+/CD45−, and CD31+/CD133+/CD45− cell types were studied by flow cytometry. Echocardiography has been performed simultaneously with the EPC measurements. We observed a significant elevation of CD34+/CD133+/CD45−, CD34+/CD105+/CD45−, and CD31+/CD133+/CD45− EPC at 7 days after PCI in comparison with 24 hours and 6 months after the MI. Patients with preserved LVEF at 7 days after PCI had also higher levels of CD31+/CD133+/CD45−. Acute anterior wall MI treated with primary PCI is followed by enhanced mobilization of EPC among which a high level of CD31+/CD133+/CD45− subtype was strongly associated with the most preserved LVEF for up to 6 months after the index event. These data may provide some insight for future therapeutic strategies.

The role of soluble HLA-G and HLA-G receptors in patients with hematological malignancies after allogeneic stem cell transplantation

Abstract HLA-G is a non-classical MHC class I molecule whose suppressive activity on immune effector cells is exerted due to interactions with receptors ILT2, ILT4 and KIR2DL4. These receptors are expressed mainly on NK cells and monocytes, and their intensity of expression changes depending on HLA-G level. HLA-G plays an important role in the development of tolerance following organ transplantations and bone marrow stem cell transplantations. HLA-G also participates in the modulation of the immune response during cancerogenesis. The aim of this study was to assess HLA-G level in blood serum, the percentage of NK cells and monocytes with expression of receptors for HLA-G (ILT2, ILT4, KIR2DL4 and NKG2D) in patients who received allogeneic stem cell transplantations, and their influence on the occurrence of graft-versus-host reaction. The study included 32 patients with bone marrow diseases (acute leukemias, myelodysplastic syndrome, chronic myeloid leukemia, paroxysmal nocturnal hemoglobinuria) who received allogeneic stem cell transplantations. We assessed the expression of receptors ILT2, ILT4, KIR2DL4 and NKG2D on monocytes and NK cells, as well as the level of HLA-G in blood serum in patients before conditioning, in the transplant hematopoietic reconstitution period following allogeneic bone marrow stem cell transplantation. The percentage of NK cells with expression of KIR2DL4, ILT2 and ILT4 receptors was higher in patients with 0–I grade GVHD than in patients with II–IV grade GVHD. The percentage of monocytes with expression of ILT4 and ILT2 receptors was higher in patients with 0–I grade GVHD than in patients with II–IV grade GVHD. The level of HLA-G in patients’ blood serum was higher after the stem cell transplantation compared with the period before transplantation. HLA-G level and HLA-G receptors are related to intensity of GVHD and may play the role of a prognostic factor for the development of GVHD and the clinical course of this reaction.

Increased expression of metalloproteinase-2 and -9 (MMP-2, MMP-9), tissue inhibitor of metalloproteinase-1 and -2 (TIMP-1, TIMP-2), and EMMPRIN (CD147) in multiple myeloma

Introduction: Activity of metalloproteinases (MMP) is controlled both by specific tissue inhibitors (TIMP) and activators (extracellular matrix metalloproteinase inducer, EMMPRIN). There are few data available concerning concentration the bone marrow of MMP-2, MMP-9, TIMP-1, and TIMP-2, or EMMPRIM expression by bone marrow mesenchymal stromal cells (BMSCs) in patients with multiple myeloma (MM). Patients and methods: We studied 40 newly diagnosed, untreated patients: 18 males and 22 females with de novo MM and 11 healthy controls. Bone marrow was collected prior to therapy. BMSCs were derived by culturing bone marrow cells on MesenCult. Protein concentrations were determined in bone marrow plasma and culture supernatants by ELISA. EMMPRIN expression by BMSCs was assessed by flow cytometry. Results: The median concentrations of MMP-9, TIMP-1, and TIMP-2 in both marrow plasma and culture supernatants were significantly higher in MM patients than controls. Conclusion: EMMPRIN expression and ratios MMP-9/TIMP-1 and MMP-2/TIMP-2 were higher in MM patients, our results demonstrate that in MM patients MMP-2 and MMP-9 are secreted in higher amounts and are not balanced by inhibitors.

Predictive factors of thrombosis for patients with essential thrombocythaemia: A single center study

BACKGROUND Thrombotembolic complications are the leading cause of mortality in essential thrombocythemia (ET), but the definition of thrombotic risk remains far from clear. OBJECTIVES The aim of this study was to evaluate the prognostic markers for thrombosis to identify ET patients at risk. MATERIAL AND METHODS Forty-five consecutive patients with ET were studied. This group was divided into two subgroups ET patients with (A) and without (B) history of thrombosis. Each patient has been tested for complete blood count, fibrinogen, factor VIII, D-dimer, protein C, APCR, TAT and F1+2. JAK2 mutation was assessed by RT-PCR. Factor V Leiden and prothrombin genes mutations were screened by DNA sequencing. RESULTS The median age of ET patients was 62.0 years. JAK2 mutation was found in 24 patients, 21 of them had a history of thrombotic events, and 17/21 were JAK2 positive. Compared to controls, ET patients had a significantly higher WBC and PLT counts, and higher mean platelet volume (MPV), but not Hgb level or RBC count. In ET subgroup A, apart from changes seen in the whole ET, the Hgb level, RBC count, and Hct were also significantly elevated. Interestingly, the MPV was significantly larger in subgroup A, but not in B. Fibrinogen and D-dimers levels were significantly higher in ET group than in controls, but not F1+F2 or TAT. The results of hemostatic tests did not markedly differ between subgroups A and B. APCR was found in 5/45 patients with ET, and 2 out of 5 had a factor V Leiden heterozygous mutation. No prothrombin gene mutation was observed. CONCLUSIONS Our results suggest that MPV can serve as a simple test for assessing the hypercoagulable state in ET patients. It has been confirmed that JAK2 mutation and leukocytosis are independent predictors for thrombotic events in ET patients.