Submitted March 3, 2006
Accepted July 10, 2007
Lentiviral-mediated RNAi inhibition of Sbds in murine hematopoietic progenitors impairs their hematopoietic potential
Amy S Rawls, Alyssa D Gregory, Jill R Woloszynek, Fulu Liu, and Daniel C Link*
Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO
* Corresponding author; email: dlink{at}im.wustl.edu.
Shwachman-Diamond Syndrome (SDS) is a rare multisystem disorder characterized by exocrine pancreatic insufficiency, multilineage hematopoietic dysfunction, and metaphyseal chondrodysplasia. Bone marrow dysfunction is present in nearly all patients with SDS, with neutropenia being the most common abnormality. The vast majority of SDS patients have mutations in the Shwachman Bodian Diamond Syndrome gene (SBDS). We have developed a strategy to examine the consequences of lentiviral-mediated RNA interference (RNAi) of Sbds on hematopoiesis. Here we report that both Sbds RNA and protein expression can be efficiently inhibited in primary murine hematopoietic cells using lentiviral-mediated RNAi. Inhibition of Sbds results in a defect in granulocytic differentiation in vitro and impairs myeloid progenitor generation in vivo. In addition, short-term hematopoietic engraftment was impaired, which is due in part to reduced homing of hematopoietic progenitors to the bone marrow. Finally, we show that inhibition of Sbds is associated with a decrease in circulating B-lymphocytes, despite evidence of normal B-lymphopoiesis. These data provide the first evidence that loss of Sbds is sufficient to induce abnormalities in hematopoiesis.
