Search results for "Thrombopoietin"

Hyper-IL-6 (H-IL-6), a Fusion Protein of Soluble IL-6 Receptor (Sil-6R), and Interleukin-6 (IL-6), Acts Synergistic with Thrombopoietin (TPO) and Ste…

1999

It has been shown that signalings from c-kit and gpl30, the signal-transducing receptor component of the IL6 receptor, act synergistic for the ex-vivo expansion of multipotential hematopoietic progenitors. A similar synergistic effect has been demonstrated for signalings from c-kit, c-mpl, and flt3. While c-kit is activated by stem cell factor (SCF), gpl30 can be activated by the complex of soluble IL-6 receptor (sIL-6R) and interleukin-6 (IL-6). Recently, a bioactive designer cytokine, H-IL-6, a fusion protein consisting of SIL-6R and IL-6 linked by a flexible peptide chain has been shown to expand human hematopoietic colony-forming cells. We tested the activity of H-IL-6 alone and in comb…

Stromal SPARC contributes to the detrimental fibrotic changes associated with myeloproliferation whereas its deficiency favors myeloid cell expansion.

2012

Abstract In myeloid malignancies, the neoplastic clone outgrows normal hematopoietic cells toward BM failure. This event is also sustained by detrimental stromal changes, such as BM fibrosis and osteosclerosis, whose occurrence is harbinger of a dismal prognosis. We show that the matricellular protein SPARC contributes to the BM stromal response to myeloproliferation. The degree of SPARC expression in BM stromal elements, including CD146+ mesenchymal stromal cells, correlates with the degree of stromal changes, and the severity of BM failure characterizing the prototypical myeloproliferative neoplasm primary myelofibrosis. Using Sparc−/− mice and BM chimeras, we demonstrate that SPARC contr…

Eltrombopag treatment for severe immune thrombocytopenia during pregnancy: a case report

2021

Primary immune thrombocytopenia (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia (platelet count <100 × 109/l) in the absence of other causes or disorders associated. The incidence of ITP in pregnancy is one to two cases per 1000 gestations. ITP could be diagnosed before or during pregnancy; sometimes a relapse of a previously diagnosed ITP can occur. Intravenous immune globulins (IVIg) and corticosteroids are the standard frontline therapy because of their well known safety profile either for the mother or for the neonate. Treatments for refractory patients are limited by potential fetal risk. We report the case of a patient with ITP along pregnancy, refractory…

Second-line administration of thrombopoietin receptor agonists in immune thrombocytopenia: Italian Delphi-based consensus recommendations

2021

Introduction: In patients with primary immune thrombocytopenia (ITP), a short course of steroids is routinely given as first-line therapy. However, the response is often transient and additional therapy is usually needed. Thrombopoietin receptor agonists (TPO-RAs) are frequently used as second-line therapy, although there is little clinical guidance on the timing of their administration and on tapering/discontinuation of the drug. To provide clinical recommendations, we used the Delphi technique to obtain consensus for statements regarding administration and on tapering/discontinuation of second-line TPO-RAs among a group of Italian clinicians with expertise in management of ITP. Methods: T…

Thrombopoietin receptor agonists in adult Evans syndrome: an international multicenter experience.

2022

Eltrombopag before procedures in patients with cirrhosis and thrombocytopenia

2012

Eltrombopag is an oral thrombopoietin-receptor agonist. This study evaluated the efficacy of eltrombopag for increasing platelet counts and reducing the need for platelet transfusions in patients with thrombocytopenia and chronic liver disease who are undergoing an elective invasive procedure.We randomly assigned 292 patients with chronic liver disease of diverse causes and platelet counts of less than 50,000 per cubic millimeter to receive eltrombopag, at a dose of 75 mg daily, or placebo for 14 days before a planned elective invasive procedure that was performed within 5 days after the last dose. The primary end point was the avoidance of a platelet transfusion before, during, and up to 7…

Gp130-signaling synergizes with FL and TPO for the long-term expansion of cord blood progenitors

1999

We investigated the effect of a new fusion protein of IL-6 and the soluble IL-6R, H-IL-6, on the long-term ex vivo expansion of hematopoietic progenitors derived from AC133+cord blood cells. H-IL-6, which acts on both IL-6Ralpha-positive and IL-6Ralpha-negative cells, effectively synergized with FL and TPO with or without SCF for the propagation of primitive progenitors. However, IL-6 showed a greater synergistic effect with FL and TPO than H-IL-6 for long-term progenitor propagation. During the first 6 weeks of culture under stroma-free serum-containing conditions, IL-6 induced a 1.96 +/- 0.64-fold higher expansion of nucleated cells, a 2.28 +/- 0.33-fold higher expansion of CD34+ cells an…

Eltrombopag in chronic hepatitis C

2014

Chronic hepatitis C is a public health problem worldwide. Unfortunately, not all patients may benefit from antiviral therapy due to thrombocytopenia. Its causes are represented by portal hypertension and platelet sequestration in the spleen, decreased serum levels or activity of thrombopoietin, the bone marrow suppression induced by hepatitis C virus and a possible adverse effect of interferon. Thrombopoietin receptor analogs may contribute to increase platelet counts in these patients. Eltrombopag binds to another region of the thrombopoietin receptor compared to endogenous thrombopoietin and stimulates the proliferation and maturation of megakaryocytes and the platelet production in a dos…

Comparison between thrombotic risk scores in essential thrombocythemia and survival implications.

2019

The conventional thrombotic risk stratification in essential thrombocythemia (ET) distinguishes patients in two risk groups based on previous thrombosis and age (< or >60). The IPSET-thrombosis takes into account four risk factors: age greater than 60 years and the presence of CV risk factors, thrombosis history and JAK2 V617F presence. The revised IPSET-thrombosis uses three adverse variables to delineate four risk categories: age greater than 60, thrombosis history, and JAK2 V617F presence. We compared different risk models in the estimation of thrombotic risk in 191 patients with ET and the role of specific driver mutations affecting overall survival, according to thrombotic risk. …

SOCS2 controls proliferation and stemness of hematopoietic cells under stress conditions and its deregulation marks unfavorable acute leukemias

2015

Abstract Hematopoietic stem cells (HSC) promptly adapt hematopoiesis to stress conditions, such as infection and cancer, replenishing bone marrow–derived circulating populations, while preserving the stem cell reservoir. SOCS2, a feedback inhibitor of JAK–STAT pathways, is expressed in most primitive HSC and is upregulated in response to STAT5-inducing cytokines. We demonstrate that Socs2 deficiency unleashes HSC proliferation in vitro, sustaining STAT5 phosphorylation in response to IL3, thrombopoietin, and GM-CSF. In vivo, SOCS2 deficiency leads to unrestricted myelopoietic response to 5-fluorouracil (5-FU) and, in turn, induces exhaustion of long-term HSC function along serial bone marro…