The DPY30 Subunit in SET1/MLL Complexes Regulates the Proliferation and Differentiation of Hematopoietic Progenitor Cells Researchers show that DPY30, a shared core subunit of the SET1/MLL family methyltransferase complexes and a facilitator of their H3K4 methylation activity, is important for ex vivo proliferation and differentiation of human CD34+ hematopoietic progenitor cells. [Blood] Abstract Runx1 Is Required for Progression of CD41+ Embryonic Precursors into HSCs but Not Prior to This Scientists report that Runx1 deficiency does not preclude formation of VE-cad+CD45−CD41+ cells, which are phenotypically equivalent to precursors of definitive hematopoietic stem cells (HSCs) but blocks transition to the subsequent CD45+ stage. [Development] Full Article IL-33-Induced Hematopoietic Stem and Progenitor Cell Mobilization Depends upon CCR2 Researchers analyzed the in vivo effect of IL-33 administration. IL-33 markedly promoted myelopoiesis in the bone marrow and myeloid cell emigration. [J Immunol] Abstract The Effects of 1,25-Dihydroxyvitamin D3 on In Vitro Human NK Cell Development from Hematopoietic Stem Cells 1,25-Dihydroxyvitamin D3 strongly induced hematopoietic stem cells to differentiate along a myeloid pathway, giving rise to CD14+ cells. [J Immunol] Abstract RIP3 Is Downregulated in Human Myeloid Leukemia Cells and Modulates Apoptosis and Caspase-Mediated p65/RelA Cleavage Researchers analyzed the expression of receptor-interacting protein kinase (RIP)1 and RIP3 in CD34+ leukemia cells from a cohort of patients with acute myeloid leukemia (AML) and CD34+ cells from healthy donors. RIP3 expression was significantly reduced in most AML samples, whereas the expression of RIP1 did not differ significantly. [Cell Death Dis] Full Article The Corepressor Tle4 Is a Novel Regulator of Murine Hematopoiesis and Bone Development Tle4 deficient hematopoietic stem cells are intrinsically defective in B lymphopoiesis and exhaust upon stress, such as serial transplantation. In the absence of Tle4 there is a profound decrease in bone mineralization. In addition, Tle4 knockout stromal cells are defective at maintaining wild-type hematopoietic stem cell function in vitro. [PLoS One] Full Article CLINICAL RESEARCH Controlled Trial of Transfusions for Silent Cerebral Infarcts in Sickle Cell Anemia Silent cerebral infarcts are the most common neurologic injury in children with sickle cell anemia and are associated with the recurrence of an infarct (stroke or silent cerebral infarct). Scientists tested the hypothesis that the incidence of the recurrence of an infarct would be lower among children who underwent regular blood-transfusion therapy than among those who received standard care. [N Engl J Med] Abstract | Press Release Good Outcome of Haploidentical Hematopoietic SCT as a Salvage Therapy in Children and Adolescents with Acquired Severe Aplastic Anemia A total of 17 children and adolescents with severe aplastic anemia underwent haploidentical hematopoietic SCT. The conditioning regimen consisted of BU, fludarabine, CY and anti-thymocyte globulin. [Bone Marrow Transplant] Abstract Early CMV Replication and Subsequent Chronic GvHD Have a Significant Anti-Leukemic Effect after Allogeneic HSCT in Acute Myeloid Leukemia Univariate analysis revealed that the factors associated with a reduction in the 5-year cumulative incidence of relapse included the first complete remission status at allogeneic hematopoietic stem cell transplantation (HSCT), non-adverse cytogenetics and molecular abnormalities, pre-transplant serum ferritin level <1,400 mg/dl, chronic graft-versus-host disease (GvHD), and early cytomegalovirus replication. [Ann Hematol] Abstract |