LABORATORY RESEARCH The IL-2/CD25 Axis Maintains Distinct Subsets of Chronic Myeloid Leukemia-Initiating Cells Using a chronic myeloid leukemia (CML)-like mouse model of myeloproliferative disease, scientists demonstrate that CML leukemia-initiating cells can be divided into CD25+FcϵRIα– Lineage marker(Lin)– Sca-1+c-Kit+ (F-LSK) cells and CD25–F–LSK cells. [Blood] Abstract Notch1 Regulates Progenitor Cell Proliferation and Differentiation during Mouse Yolk Sac Hematopoiesis Researchers report the consequences of Notch gain-of-function in mouse embryo hematopoiesis, achieved by constitutive expression of Notch1 intracellular domain in angiopoietin receptor tyrosine kinase receptor-2-derived enhanced green fluorescence protein hematovascular progenitors. [Cell Death Differ] Abstract MiRNA-23a Mediates Post-Transcriptional Regulation of CXCL12 in Bone Marrow Stromal Cells Scientists determined that microRNA-23a (miR-23a) is predicted to bind to the 3-UTR and is strongly expressed in primary bone marrow stromal cells. Modulation of miR-23a changes the migratory potential of hematopoietic progenitor cells in co-culture experiments. [Haematologica] Abstract | Full Article BMI1 Reprograms Histone Acetylation and Enhances c-Fos Pathway via Directly Binding to Zmym3 in Malignant Myeloid Progression In vitro gene transfection studies showed that BMI1 inhibited cell myeloid and erythroid differentiation induced by 12-O-tetradecanoyl phorbol-13-acetate and histone deacetylase inhibitor sodium butyrate respectively. [J Cell Mol Med] Full Article Cooperative Interaction of Etv2 and Gata2 Regulates the Development of Endothelial and Hematopoietic Lineages Researchers demonstrated that Gata2 is co-expressed and interacts with Etv2 in the endothelial and hematopoietic cells in the early stages of embryogenesis. [Dev Biol] Abstract Acute Lymphoid Leukemia Cells with Greater Stem Cell Antigen-1 (Ly6a/Sca-1) Expression Exhibit Higher Levels of Metalloproteinase Activity and Are More Aggressive In Vivo Investigators explored the impact of expression of this stem cell associated gene in acute lymphoid leukemia. Higher levels of Ly6a/Sca-1 expression led to more aggressive leukemia growth in vivo and earlier death of hosts. [PLoS One] Full Article Age Dependence of Hematopoietic Progenitor Survival and Chemokine Family Gene Induction after Gamma Irradiation in Bone Marrow Tissue in C3H/He Mice Scientists examined the radiation response of hematopoietic stem and progenitor cells in infant, juvenile, and adult C3H/He mice, which are susceptible to radiation-induced myeloid leukemia. [Radiat Res] Abstract CLINICAL RESEARCH Ultra Low-Dose IL-2 for GVHD Prophylaxis after Allogeneic HSCT Mediates Expansion of Regulatory T Cells without Diminishing Anti-Viral and Anti-Leukemic Activity Investigators prospectively evaluated the effects of ultra low-dose IL-2 injections on regulatory T-cell (Treg) recovery in pediatric patients after allogeneic hematopoietic stem cell transplantation (alloSCT) and compared this recovery with Treg reconstitution post alloSCT in patients without IL-2. [Clin Cancer Res] Abstract Alternative Donor Transplantation for Older Patients with Acute Myeloid Leukemia in First Complete Remission: A CIBMTR-Eurocord Analysis Researchers studied AML patients over age 50 in CR1 after adult unrelated donor or umbilical cord blood (UCB) transplantations. UCB recipients less often achieved CR1 within 8 weeks, more often received reduced-intensity conditioning, and cyclosporin-based graft-versus-host disease prophylaxis. [Biol Blood Marrow Transplant] Abstract |