Maintenance of hematopoietic stem cells by tyrosine-unphosphorylated STAT5 and JAK inhibition
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA927279 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Adult hematopoietic stem cells (HSCs) are responsible for the lifelong production of blood and immune cells and must respond to extracellular cues including cytokines. The JAK/STAT pathway is a highly conserved pathway, activated by many cytokines, in which tyrosine-phosphorylated STATs (pSTATs) function as transcription factors. STAT5 is a pivotal downstream mediator of several cytokines known to regulate hematopoiesis but its function in the HSC compartment remains poorly understood. Here we show that STAT5-deficient HSCs exhibited an unusual phenotype - reduced multi-lineage repopulation and self-renewal combined with reduced cell cycle entry and increased differentiation. This reflected not only loss of a canonical pSTAT5 transcriptional program but also loss of distinct functions mediated by tyrosine-unphosphorylated STAT5 (uSTAT5). Consistent with this concept expression of an unphosphorylatable STAT5B mutant constrained HSC differentiation, promoted HSC maintenance and upregulated transcriptional programs associated with quiescence and stemness. Moreover, treatment with a JAK1/2 inhibitor (ruxolitinib) increased the uSTAT5:pSTAT5 ratio, constrained HSC differentiation and proliferation and promoted HSC maintenance, thus phenocopying uSTAT5B overexpression. Our results therefore reveal a previously unrecognized interplay between pSTAT5 and uSTAT5 in the control of HSC function. In addition the demonstration that JAK inhibition promotes HSC maintenance has implications for gene therapy using HSCs and may contribute to the failure of JAK inhibitors to eradicate myeloproliferative neoplasms.
2024-01-31 | GSE223680 | GEO
Project description:Adult haematopoietic stem cells (HSCs) are responsible for the lifelong production of blood and immune cells and must respond to extracellular cues including cytokines. The JAK/STAT pathway is a highly conserved pathway, activated by many cytokines, in which tyrosine-phosphorylated STATs (pSTATs) function as transcription factors. STAT5 is a pivotal downstream mediator of several cytokines known to regulate haematopoiesis but its function in the HSC compartment remains poorly understood. Here we show that STAT5-deficient HSCs exhibited an unusual phenotype - reduced multi-lineage repopulation and self-renewal combined with reduced cell cycle entry and increased differentiation. This reflected not only loss of a canonical pSTAT5 transcriptional program but also loss of distinct functions mediated by tyrosine-unphosphorylated STAT5 (uSTAT5). Consistent with this concept expression of an unphosphorylatable STAT5B mutant constrained HSC differentiation, promoted HSC maintenance and upregulated transcriptional programs associated with quiescence and stemness. Moreover, treatment with a JAK1/2 inhibitor (ruxolitinib) increased the uSTAT5:pSTAT5 ratio, constrained HSC differentiation and proliferation and promoted HSC maintenance, thus phenocopying uSTAT5B overexpression. Our results therefore reveal a previously unrecognized interplay between pSTAT5 and uSTAT5 in the control of HSC function. In addition the demonstration that JAK inhibition promotes HSC maintenance has implications for gene therapy using HSCs and may contribute to the failure of JAK inhibitors to eradicate myeloproliferative neoplasms.
2024-05-29 | GSE223366 | GEO
Project description:Adult haematopoietic stem cells (HSCs) are responsible for the lifelong production of blood and immune cells and must respond to extracellular cues including cytokines. The JAK/STAT pathway is a highly conserved pathway, activated by many cytokines, in which tyrosine-phosphorylated STATs (pSTATs) function as transcription factors. STAT5 is a pivotal downstream mediator of several cytokines known to regulate haematopoiesis but its function in the HSC compartment remains poorly understood. Here we show that STAT5-deficient HSCs exhibited an unusual phenotype - reduced multi-lineage repopulation and self-renewal combined with reduced cell cycle entry and increased differentiation. This reflected not only loss of a canonical pSTAT5 transcriptional program but also loss of distinct functions mediated by tyrosine-unphosphorylated STAT5 (uSTAT5). Consistent with this concept expression of an unphosphorylatable STAT5B mutant constrained HSC differentiation, promoted HSC maintenance and upregulated transcriptional programs associated with quiescence and stemness. Moreover, treatment with a JAK1/2 inhibitor (ruxolitinib) increased the uSTAT5:pSTAT5 ratio, constrained HSC differentiation and proliferation and promoted HSC maintenance, thus phenocopying uSTAT5B overexpression. Our results therefore reveal a previously unrecognized interplay between pSTAT5 and uSTAT5 in the control of HSC function. In addition the demonstration that JAK inhibition promotes HSC maintenance has implications for gene therapy using HSCs and may contribute to the failure of JAK inhibitors to eradicate myeloproliferative neoplasms.
2024-05-29 | GSE223632 | GEO
Project description:Maintenance of ESLAM haematopoietic stem cells by tyrosine-unphosphorylated STAT5 and JAK inhibition
| PRJNA925879 | ENA
Project description:Maintenance of haematopoietic stem cells by tyrosine-unphosphorylated STAT5 and JAK inhibition - STAT5 deficient HSPCs (LK)
| PRJNA926999 | ENA
Project description:STAT5 proteins are vital for lymphocyte development and function. Tyrosine phosphorylation of a C-terminal tyrosine is the key event in cytokine activation of STAT5A and STAT5B. However, the role of STAT5 tyrosine phosphorylation has not been assessed in vivo. Here we generated Stat5a and Stat5b tyrosine mutant knock-in (KI) mice and found that these animals had greatly reduced CD8+ T cell numbers. These cells exhibited profoundly diminished proliferation in response to IL-2, correlating with greatly reduced IL-2-induced pRB and a block in the G1-->S phase transition. The mutant cells also exhibited decreased IL-2-mediated activation of pERK and pAKT, which can in part be attributed to diminished IL-2-induced expression of IL-2R-beta and IL-2R-gamma. Our findings highlight that the tyrosine phosphorylation of both STAT5A and STAT5B is essential for maximal IL-2 signaling and elucidate the molecular basis for achieving an optimal mitogenic effect of IL-2 on CD8+ T cells.
2023-11-06 | MSV000093320 | MassIVE
Project description:STAT5 proteins are vital for lymphocyte development and function. Tyrosine phosphorylation of a C-terminal tyrosine is the key event in cytokine activation of STAT5A and STAT5B. However, the role of STAT5 tyrosine phosphorylation has not been assessed in vivo. Here we generated Stat5a and Stat5b tyrosine mutant knock-in (KI) mice and found that these animals had greatly reduced CD8+ T cell numbers. These cells exhibited profoundly diminished proliferation in response to IL-2, correlating with greatly reduced IL-2-induced pRB and a block in the G1-->S phase transition. The mutant cells also exhibited decreased IL-2-mediated activation of pERK and pAKT, which can in part be attributed to diminished IL-2-induced expression of IL-2R-beta and IL-2R-gamma. Our findings highlight that the tyrosine phosphorylation of both STAT5A and STAT5B is essential for maximal IL-2 signaling and elucidate the molecular basis for achieving an optimal mitogenic effect of IL-2 on CD8+ T cells. [doi:10.25345/C5833N851] [dataset license: CC0 1.0 Universal (CC0 1.0)]
2023-12-23 | MSV000093724 | MassIVE
Project description:Adult haematopoietic stem cells (HSCs) are responsible for the lifelong production of blood and immune cells and must respond to extracellular cues including cytokines. The JAK/STAT pathway is a highly conserved pathway, activated by many cytokines, in which tyrosine-phosphorylated STATs (pSTATs) function as transcription factors. STAT5 is a pivotal downstream mediator of several cytokines known to regulate haematopoiesis but its function in the HSC compartment remains poorly understood. Here we show that STAT5-deficient HSCs exhibited an unusual phenotype - reduced multi-lineage repopulation and self-renewal combined with reduced cell cycle entry and increased differentiation. This reflected not only loss of a canonical pSTAT5 transcriptional program but also loss of distinct functions mediated by tyrosine-unphosphorylated STAT5 (uSTAT5). Consistent with this concept expression of an unphosphorylatable STAT5B mutant constrained HSC differentiation, promoted HSC maintenance and upregulated transcriptional programs associated with quiescence and stemness. Moreover, treatment with a JAK1/2 inhibitor (ruxolitinib) increased the uSTAT5:pSTAT5 ratio, constrained HSC differentiation and proliferation and promoted HSC maintenance, thus phenocopying uSTAT5B overexpression. Our results therefore reveal a previously unrecognized interplay between pSTAT5 and uSTAT5 in the control of HSC function. In addition the demonstration that JAK inhibition promotes HSC maintenance has implications for gene therapy using HSCs and may contribute to the failure of JAK inhibitors to eradicate myeloproliferative neoplasms. To evaluate the long-term functional capacity of uSTAT5B overexpressing HSCs, WT CD45.2 ESLAM HSCs were sorted and transduced with lentivirus containing STAT5B-YF, STAT5B-WT and EV in SCF and IL-11 cultures. Five days after infection, cells were sorted for viability (DAPI-, Thermo Fisher) and green fluorescent protein (GFP) expression and processed according to the manufacturer’s protocol for 10x Chromium (10x Genomics, Pleasanton, CA) experiments .
2024-05-29 | GSE260462 | GEO
Project description:The transcription factors STAT5A and STAT5B are essential downstream mediators of many tyrosine kinases, particularly in hematopoietic cancers. As such, STAT5 is activated by FLT3-ITD, which is a constitutively active tyrosine kinase driving the pathogenesis of acute myeloid leukemia (AML). Since STAT5 is a critical mediator of diverse malignant properties of AML cells, direct targeting of STAT5 function is of significant clinical value. Here, we describe the novel small molecular weight inhibitor AC-4-130 that directly binds to the phosphotyrosine (pY)-binding pocket of the STAT5 SH2 domain, thereby disrupting STAT5 activation, dimerization, nuclear translocation, and STAT5-dependent induction of gene transcription. AC-4-130 substantially impaired the proliferation and clonogenic growth of human AML cell lines and primary FLT3-ITD+ AML patient cells in vitro and in vivo. Importantly, AC-4-130 synergistically increased the cytotoxicity of the JAK1/2 inhibitor Ruxolitinib and the p300/pCAF inhibitor Garcinol. In summary, we report the development and preclinical evaluation of a novel, potent STAT5 SH2 domain inhibitor that can efficiently block pathological levels of STAT5 activity in AML. The synergistic effects of AC-4-130 tyrosine kinase inhibitors as well as emerging treatment strategies provide new opportunities for combinatorial treatment of leukemia and potentially other cancers.
2018-09-03 | GSE103510 | GEO
Project description:We also show that OSM is sufficient for maintaining quiescence of hair follicle stem cells (HFSCs), and OSMRβ-JAK-STAT5 signaling is necessary for maintaining the resting phase of the hair cycle (telogen). Using single-cell RNA sequencing, we identify the source of OSM to be a distinct subset of TREM2+ macrophages that predominate during early telogen. Moreover, inhibition of macrophages during telogen by genetic ablation, neutralizing antibodies and small-molecule inhibitors was sufficient to induce anagen.
2019-04-09 | GSE108709 | GEO