Objective: In a previous study, we found increased plasma soluble receptor for interleukin-6 (sIL-6R) levels in patients with essential thrombocythemia (ET) that could promote megakaryopoiesis through IL-6 binding and further interaction with the signal transducer gp130. Here we have searched for the cell source of sIL-6R within mononuclear cells in these patients and the underlying abnormalities involved in its overproduction.
Materials And Methods: Thirty patients with the diagnosis of ET were studied.
Objectives: To evaluate the frequency of MPL W515L, W515K and S505N mutations in essential thrombocythemia (ET) and primary myelofibrosis (PMF) and to determine whether MPLW515L leads to impaired Mpl expression, constitutive STAT3 and STAT5 activation and enhanced response to thrombopoietin (TPO).
Methods: Mutation detection was performed by allele-specific PCR and sequencing. Platelet Mpl expression was evaluated by flow cytometry, immunoblotting and real-time RT-PCR.
This study investigated the involvement of chemokines including stromal derived factor 1 (SDF-1), interleukin 8 (IL-8), growth-related oncogene alpha (GRO-alpha) and their receptors, CXCR4, CXCR2 and CXCR1 in essential thrombocythemia (ET), a chronic myeloproliferative disease characterized by megakaryocytic hyperplasia and high platelet count. Fifty-three ET patients were studied. Plasma levels of SDF-1, IL-8 and GRO-alpha, evaluated by enzyme-linked immunosorbent assay, and flow cytometric analysis of CXCR1 and CXCR2 on the platelet membrane, were found to be normal in ET patients.
View Article and Find Full Text PDFObjective: JAK2V617F mutation rate in granulocytes from essential thrombocythemia (ET) patients ranges from 12% to 57%. Our aim was to evaluate the frequency of this mutation in the megakaryocyte/platelet lineage, and to analyze its clinical associations in ET. In addition, we determined whether this mutation leads to constitutive phosphorylation of STAT5 in platelets.
View Article and Find Full Text PDFInterleukin 6 is a multifunctional cytokine that exerts its biological activity through binding to an 80 Kd specific receptor (IL-6Ralpha) and a 130 Kd signal-transducing unit (gp130). A 55 Kd soluble IL-6R (IL-6sR) has also been described which, after binding to IL-6 is also able to activate gp130. The presence of IL-6Ralpha was described in some megakaryoblastic cell lines but is still controversial in normal megakaryocytes.
View Article and Find Full Text PDFA working scheme developed in our laboratory for identification (by species group and species) of coagulase-negative staphylococci (CNS) was evaluated with 201 consecutive isolates and then validated by using the reference method of Kloos and Schleifer (W. E. Kloos and K.
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