1. JAK2-V617F and interferon-α induce megakaryocyte-biased stem cells characterized by decreased long-term functionality
- Author
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Jan Stetka, Nouraiz Ahmed, Christian Beisel, Damien Luque Paz, Nils Hansen, Julian Hilfiker, Dominik Wolf, Steffen Koschmieder, Florian Geier, Hui Hao-Shen, Milena Kalmer, Stefan Dirnhofer, Tim H. Brümmendorf, Tata Nageswara Rao, Lucia Kubovcakova, Timm Schroeder, Max Endele, Margareta Rybarikova, and Radek C. Skoda
- Subjects
Platelet Membrane Glycoprotein IIb ,Immunology ,Plenary Paper ,Mice, Transgenic ,Biochemistry ,Antiviral Agents ,Flow cytometry ,Mice ,Megakaryocyte ,Interferon ,Gene expression ,medicine ,Animals ,Point Mutation ,Humans ,Gene Knock-In Techniques ,Myeloproliferative Disorders ,medicine.diagnostic_test ,Chemistry ,Interferon-alpha ,hemic and immune systems ,Cell Biology ,Hematology ,Janus Kinase 2 ,Cell cycle ,Hematopoietic Stem Cells ,Molecular biology ,Transplantation ,Haematopoiesis ,medicine.anatomical_structure ,Interferons ,Stem cell ,Megakaryocytes ,medicine.drug - Abstract
We studied a subset of hematopoietic stem cells (HSCs) that are defined by elevated expression of CD41 (CD41hi) and showed bias for differentiation toward megakaryocytes (Mks). Mouse models of myeloproliferative neoplasms (MPNs) expressing JAK2-V617F (VF) displayed increased frequencies and percentages of the CD41hi vs CD41lo HSCs compared with wild-type controls. An increase in CD41hi HSCs that correlated with JAK2-V617F mutant allele burden was also found in bone marrow from patients with MPN. CD41hi HSCs produced a higher number of Mk-colonies of HSCs in single-cell cultures in vitro, but showed reduced long-term reconstitution potential compared with CD41lo HSCs in competitive transplantations in vivo. RNA expression profiling showed an upregulated cell cycle, Myc, and oxidative phosphorylation gene signatures in CD41hi HSCs, whereas CD41lo HSCs showed higher gene expression of interferon and the JAK/STAT and TNFα/NFκB signaling pathways. Higher cell cycle activity and elevated levels of reactive oxygen species were confirmed in CD41hi HSCs by flow cytometry. Expression of Epcr, a marker for quiescent HSCs inversely correlated with expression of CD41 in mice, but did not show such reciprocal expression pattern in patients with MPN. Treatment with interferon-α further increased the frequency and percentage of CD41hi HSCs and reduced the number of JAK2-V617F+ HSCs in mice and patients with MPN. The shift toward the CD41hi subset of HSCs by interferon-α provides a possible mechanism of how interferon-α preferentially targets the JAK2 mutant clone. © 2021 American Society of Hematology ISSN:0006-4971 ISSN:1528-0020
- Published
- 2021