Endothelial Injury Syndromes after Allogeneic Hematopoietic Stem Cell Transplantation: Angiopetin-2 as a Novel Predictor of the Outcome and the Role of Functional Autoantibodies against Angiotensin II Type 1 and Endothelin A Receptor.

Transplant-associated thrombotic microangiopathy (TMA) occurs in a significant percentage of patients after allogeneic stem cell transplantation (allo-SCT) and is associated with significant morbidity and mortality. The aim of the present study was to examine the association of serum angiopoetin-2 (Ang2) levels and the presence of antibodies against angiotensin II type 1 (AT1R) and ndothelin A Recreptor (ETAR) with the outcome of patients with TMA and/or graft-versus-host disease (GVHD) after allo-SCT. Analysis of our data showed that elevated serum Ang2 levels at the time of TMA diagnosis are significantly associated with increased non-relapse mortality and decreased overall survival.

Paroxysmal nocturnal hemoglobinuria: Where are we going.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare nonmalignant clonal hematological disorder that is characterized by a deficiency of the GPI-linked complement regulators on the membrane of hematopoietic cells, which renders them susceptible to complement-mediated damage. Intravascular hemolysis (IVH), increased tendency for thrombosis, and bone marrow failure constitutes hallmark features of the disease and are associated with high morbidity and mortality. The introduction of C5 inhibitors radically changed disease outcomes, offering a near-normal life expectancy to PNH patients.

Endothelial Dysfunction Syndromes after Allogeneic Stem Cell Transplantation.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the only therapy with a curative potential for a variety of malignant and non-malignant diseases. The major limitation of the procedure is the significant morbidity and mortality mainly associated with the development of graft versus host disease (GVHD) as well as with a series of complications related to endothelial injury, such as sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), transplant-associated thrombotic microangiopathy (TA-TMA), etc. Endothelial cells (ECs) are key players in the maintenance of vascular homeostasis and during allo-HSCT are confronted by multiple challenges, such as the toxicity from conditioning, the administration of calcineurin inhibitors, the immunosuppression associated infections, and the donor alloreactivity against host tissues.

Transplant-Associated Thrombotic Microangiopathy in the Context of Allogenic Hematopoietic Stem Cell Transplantation: Where We Stand.

Transplant-associated thrombotic microangiopathy (TA-TMA) constitutes a significant contributor to the increased morbidity and mortality after allogenic hematopoietic stem cell transplantation (allo-HSCT). TA-TMA is a heterogenous disease, characterized by the triad of endothelial cell activation, complement dysregulation and microvascular hemolytic anemia, which may affect all organs. The lack of consensus diagnostic criteria, along with the common clinical features mimicking other diseases that complicate allo-HSCT, make the diagnosis of TA-TMA particularly challenging.

Extracellular Vesicles in Haematological Disorders: A Friend or a Foe?

Extracellular vesicles (EVs) have emerged as important mediators of homeostasis, immune modulation and intercellular communication. They are released by every cell of the human body and accordingly detected in a variety of body fluids. Interestingly, their expression can be upregulated under various conditions, such as stress, hypoxia, irradiation, inflammation, etc.

A 'waste product' to save the day in the field of transplantation: The evolving potential of extracellular vesicles.

Graft rejection and graft-versus-host disease constitute the leading causes of morbidity and early mortality after solid organ and haematopoietic stem cell transplantation, respectively. Despite the current advances in immunotherapy, their incidence remains significant, underlying the need for new therapies to be developed. Extracellular vesicles (EV), and particularly small EV (sEV), have emerged as significant mediators of intercellular communication and immune modulation.

Autologous stem cell transplantation for multiple myeloma patients with chronic kidney disease: a safe and effective option.

Chronic Kidney Disease (CKD) is a frequent complication in patients with multiple myeloma (MM) and is associated with adverse outcomes. The use of autologous stem cell transplantation (ASCT) has improved disease outcomes, however, the safety and efficacy of ASCT in patients with CKD has been the subject of debate. To investigate this, we conducted a retrospective analysis of 370 MM patients who underwent their first ASCT, including those with mild, moderate and severe CKD as well as normal renal function at the time of transplant.

A Novel, Cell-Free Therapy to Enter Our Hearts: The Potential Role of Small EVs in Prevention and Treatment of CVD.

Heart disease constitutes one of the leading causes of morbidity and mortality worldwide. Current therapeutic techniques, such as interventional revascularization, although lifesaving, come along with myocardial injury related to the reperfusion itself, called ischemia-reperfusion injury, which is an added factor for increased morbidity. For that reason, there is an imperative need for novel therapies to be developed that would either prevent or treat myocardial injury.

Identification of a novel HLA-G+ regulatory population in blood: expansion after allogeneic transplantation and de novo HLA-G expression at graft-versus-host disease sites.

Background: The human leukocyte antigen-G (HLA-G) has been considered to be an important tolerogeneic molecule playing an essential role in maternal-fetal tolerance, which constitutes the perfect example of successful physiological immunotolerance of semi-allografts. In this context, we investigated the putative role of this molecule in the allogeneic hematopoietic cell transplantation setting.

Design And Methods: The percentage of HLA-G(+) cells in peripheral blood of healthy donors and allo-transplanted patients was evaluated by flow cytometry.