Summary

Myelofibrosis is a severe myeloproliferative neoplasm characterized by increased numbers of abnormal bone marrow megakaryocytes that induce fibrosis, destroying the hematopoietic microenvironment. To determine the cellular and molecular basis for aberrant megakaryopoiesis in myelofibrosis, we performed single-cell transcriptome profiling of 135,929 CD34+ lineage- hematopoietic stem and progenitor cells (HSPCs), single-cell proteomics, genomics, and functional assays. We identified a bias toward megakaryocyte differentiation apparent from early multipotent stem cells in myelofibrosis and associated aberrant molecular signatures. A sub-fraction of myelofibrosis megakaryocyte progenitors (MkPs) are transcriptionally similar to healthy-donor MkPs, but the majority are disease specific, with distinct populations expressing fibrosis- and proliferation-associated genes. Mutant-clone HSPCs have increased expression of megakaryocyte-associated genes compared to wild-type HSPCs, and we provide early validation of G6B as a potential immunotherapy target. Our study paves the way for selective targeting of the myelofibrosis clone and illustrates the power of single-cell multi-omics to discover tumor-specific therapeutic targets and mediators of tissue fibrosis.

Overall design

We used 10x genomics platform to profile single-cell transcriptome of CD34+Lineage- hematopoietic stem/progenitor cells (HSPCs) derived from 15 human myelofibrosis tissue samples and 6 healthy donors

Contributors

Bethan Psaila 1, Guanlin Wang 2, Alba Rodriguez-Meira 2, Rong Li 3, Elisabeth F Heuston 4, Lauren Murphy 3, Daniel Yee 5, Ian S Hitchcock 5, Nikolaos Sousos 3, Jennifer O'Sullivan 3, Stacie Anderson 6, Yotis A Senis 7, Olga K Weinberg 8, Monica L Calicchio 8; NIH Intramural Sequencing Center 9; Deena Iskander 10, Daniel Royston 11, Dragana Milojkovic 10, Irene Roberts 12, David M Bodine 4, Supat Thongjuea 13, Adam J Mead 14

Contact

adam.mead@imm.ox.ac.uk.(Adam J Mead)