Cellular Reprogramming Allows Generation of Autologous Hematopoietic Progenitors From AML Patients That Are Devoid of Patient-Specific Genomic Aberrations

Abstract

Current treatments that use hematopoietic progenitor cell (HPC) transplantation in acute myeloid leukemia (AML) patients substantially reduce the risk of relapse, but are limited by the availability of immune compatible healthy HPCs. Although cellular reprogramming has the potential to provide a novel autologous source of HPCs for transplantation, the applicability of this technology toward the derivation of healthy autologous hematopoietic cells devoid of patient-specific leukemic aberrations from AML patients must first be evaluated. Here, we report the generation of human AML patient-specific hematopoietic progenitors that are capable of normal in vitro differentiation to myeloid lineages and are devoid of leukemia-associated aberration found in matched patient bone marrow. Skin fibroblasts were obtained from AML patients whose leukemic cells possessed a distinct, leukemia-associated aberration, and used to create AML patient-specific induced pluripotent stem cells (iPSCs). Through hematopoietic differentiation of AML patient iPSCs, coupled with cytogenetic interrogation, we reveal that AML patient-specific HPCs possess normal progenitor capacity and are devoid of leukemia-associated mutations. Importantly, in rare patient skin samples that give rise to mosaic fibroblast cultures that continue to carry leukemia-associated mutations; healthy hematopoietic progenitors can also be generated via reprogramming selection. Our findings provide the proof of principle that cellular reprogramming can be applied on a personalized basis to generate healthy HPCs from AML patients, and should further motivate advances toward creating transplantable hematopoietic stem cells for autologous AML therapy. Stem Cells 2013;33:1839–1849

Letter to the Editor: Production of Mature Healthy Hematopoietic Cells from Induced Pluripotent Stem Cells Derived from an AML Diagnostic Sample Containing the t(8;21) Translocation

“…In agreement with Salci et al [1], we also found that only "healthy" patient-specific iPSCs were generated from AML patient cells. Both studies support the idea that the reprogramming process may be biased against certain leukemiaspecific genetic aberrations.…”

“…None of the known leukemiaassociated genetic aberrations present in four primary AML samples was detected in any of the corresponding patient-specific iPSC or HPCs differentiated from iPSC clones [1]. This work represents an exciting advance for the field of autologous transplantation in AML treatment, especially considering the reduced risk of transplanting leukemia cells back into the patient.…”

“…Salci et al [1] recently demonstrated the possibility of using induced pluripotent stem cell (iPSC) technology to generate healthy hematopoietic progenitor cells (HPC) from skin fibroblasts procured from acute myeloid leukemia (AML) patients. None of the known leukemiaassociated genetic aberrations present in four primary AML samples was detected in any of the corresponding patient-specific iPSC or HPCs differentiated from iPSC clones [1].…”

Brief Report: Human Acute Myeloid Leukemia Reprogramming to Pluripotency Is a Rare Event and Selects for Patient Hematopoietic Cells Devoid of Leukemic Mutations

“…Upon thawing, CD34+ enrichment was performed using human CD34 MicroBead Kit (Miltenyi Biotec, Bergisch Gladbach, Germany) and then AML samples were cultured in hematopoietic medium: Iscove's Modified, Dulbecco's Media (IMDM) with 15% v/v BSA (Bovine Serum Albumin), Insulin, and Transferrin (BIT) (StemCell Technologies Vancouver, Canada), 1% v/v Non‐Essential Amino Acids (NEAA), and 1% v/v Na‐pyruvate (Gibco, Grand Island, NY), 100 ng/ml Flt‐3 ligand, 20 ng/ml interleukin‐3, and 100 ng/ml thrombopoietin (all (R&D Systems, Minneapolis, MN)) and 100 ng/ml stem cell factor (Amgen Inc., Thousand Oaks, CA) for 24 to 48 hours before transduction. During reprogramming, AML samples were cultured on irradiated mouse embryonic fibroblasts (iMEFs) in reprogramming media supplemented either with 10 ng/ml human fibroblast growth factor (FGF) 2 (R&D systems), or 20 ng/ml human leukemia inhibitory factor (LIF, ThermoFisher), PD0325901 (1 μM), and CHIR99021 (3 μM, (Selleckchem, Houston, TX)), herein termed FGF 2 and LIF‐2i media , respectively. iPSCs were differentiated into hematopoietic progenitor cells (HPCs) as described previously .…”

“…Fluorescence in situ hybridization was performed on AML, iPSC, and colony‐forming unit (CFU) samples, as described previously . Number of nuclei scored is indicated in figure legends.…”