Multicellular derived S100A8/A9 maintains megakaryocytes in an immature state in immune thrombocytopenia.
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus Homo sapiens
PROVIDER: GSE275370 | GEO | 2026/05/15
REPOSITORIES: GEO
Similar Datasets
Project description:Immune thrombocytopenia (ITP) is a complicated bleeding disease characterized by sharp platelet reduction. As a dominating element involved in ITP, megakaryocytes (MKs) are responsible for thrombopoiesis. However, the mechanism behind the dysregulation of thrombopoiesis in ITP remains undetermined. In this study, we examined the role of YAP1, Yes-associated protein 1, in thrombopoiesis during ITP. We observed a reduced YAP1 expression with cytoskeletal actin misalignment in MKs of ITP patients. Using experimental ITP mice, we showed that YAP1 reduction induced aberrant MK distribution, reduced the percentage of late MKs in total MKs, and caused submaximal platelet recovery. Mechanistically, YAP1 upregulation by GATA1 binding to its promoter promoted MK maturation. Phosphorylated YAP1 facilitated cytoskeletal activation by binding of its WW2 domain to MYH9, facilitating thrombopoiesis. Targeting YAP1 by its activator XMU-MP-1 was sufficient to rescue cytoskeleton defects and thrombopoiesis in YAP1+/- ITP mice and ITP patients. Taken together, these results demonstrate a crucial role for YAP1 in thrombopoiesis, providing a potential for the development of diagnostic markers and therapeutic options for ITP.
2024-12-22 | GSE250220 | GEO
Project description:Immune thrombocytopenia (ITP) is a complicated bleeding disease characterized by sharp platelet reduction. As a dominating element involved in ITP, megakaryocytes (MKs) are responsible for thrombopoiesis. However, the mechanism behind the dysregulation of thrombopoiesis in ITP remains undetermined. In this study, we examined the role of YAP1, Yes-associated protein 1, in thrombopoiesis during ITP. We observed a reduced YAP1 expression with cytoskeletal actin misalignment in MKs of ITP patients. Using experimental ITP mice, we showed that YAP1 reduction induced aberrant MK distribution, reduced the percentage of late MKs in total MKs, and caused submaximal platelet recovery. Mechanistically, YAP1 upregulation by GATA1 binding to its promoter promoted MK maturation. Phosphorylated YAP1 facilitated cytoskeletal activation by binding of its WW2 domain to MYH9, facilitating thrombopoiesis. Targeting YAP1 by its activator XMU-MP-1 was sufficient to rescue cytoskeleton defects and thrombopoiesis in YAP1+/- ITP mice and ITP patients. Taken together, these results demonstrate a crucial role for YAP1 in thrombopoiesis, providing a potential for the development of diagnostic markers and therapeutic options for ITP.
2024-12-31 | GSE251704 | GEO
Project description:Purpose and Methods: Immune thrombocytopenia (ITP), an autoimmune disorder, is mainly caused by megakaryocyte dysfunction, although the underlying mechanisms remain unclear. Here, we performed single-cell transcriptome profiling of bone marrow (BM) CD34+ hematopoietic stem and progenitor cells (HSPCs) to determine defects in megakaryopoiesis in ITP. Results: Gene expression, cell-cell interactions, and transcriptional regulatory networks varied in HSPCs of ITP, particularly in natural killer/T cell progenitors and a pre-B cell subset, highlighting the selective immune aberratixon associated with defective megakaryopoiesis in ITP. CD9 can be used to enrich megakaryocyte-biased HSPCs, and CD9+Lin−CD34+CD45RA− HSPCs have the potential to be novel diagnostic and therapeutic targets in ITP. Further analysis revealed that megakaryocytic progenitors (MkP) can be divided into seven subclusters with different gene expression patterns and functions. The ITP-associated DEGs were MkP subtype-specific, with most DEGs concentrated in the subcluster possessing dual functions of immunomodulation and platelet generation. Conclusions: This study comprehensively dissects defective hematopoiesis and provides novel therapeutic targets for ITP.
2022-09-03 | GSE196676 | GEO
Project description:Immune thrombocytopenia (ITP) is a common platelet disorder in pediatric patients. Pediatric and adult ITP have been associated with sialic acid alterations, but the pathophysiology of ITP remains elusive, and ITP is often a diagnosis of exclusion. Our analysis of pediatric ITP plasma samples showed increased anti-Thomsen-Friedenreich antigen (TF-antigen) antibody representation, suggesting increased exposure of the typically sialylated and cryptic TF-antigen in these patients. The O-glycan sialyltransferase St3gal1 add sialic acid specifically on the TF-antigen. To understand if TF-antigen exposure associates with thrombocytopenia, we generated a mouse model with targeted deletion of St3gal1 in megakaryocytes (MK) (St3gal1MK-/-). TF-antigen exposure was restricted to MKs and resulted in thrombocytopenia. Deletion of Jak3 in St3gal1MK-/- mice normalized platelet counts implicating involvement of immune cells. Interferon-producing Siglec H-positive bone marrow (BM) immune cells engaged with O-glycan sialic acid moieties to regulate type I interferon (IFN-I) secretion and platelet release (thrombopoiesis), as evidenced by partially normalized platelet count following and inhibition of interferon and Siglec H receptors. Single cell RNAseq determined that TF-antigen exposure by MKs primed St3gal1MK-/- BM immune cells to release IFN-I. Single cell RNAseq further revealed a new population of immune cells with a plasmacytoid dendritic cell (pDC)-like signature and concomitant upregulation of immunoglobulin re-arrangement gene transcripts Igkc and Ighm, suggesting additional immune regulatory mechanisms. Thus, aberrant TF-antigen moieties, often found in pathological conditions, regulate immune cells and thrombopoiesis in the BM, leading to reduced platelet count.
2021-06-29 | GSE179067 | GEO
Project description:We investigated the expression profiles of plasma miRNAs in immune thrombocytopenia (ITP) patients. Peripheral blood plasma was used for Agilent miRNA expression microarray analysis to define miRNA profiles and to identify miRNAs with discriminatory levels for ITP and healthy controls. Results were further validated using quantitative realtime PCR on a larger cohort, enabling relative quantification of plasma miRNAs and defining miRNAs with diagnostic value for the disease.
2017-12-31 | GSE80401 | GEO
Project description:High ploidy large cytoplasmic megakaryocytes (LCM) are critical negative regulators of hematopoietic stem cells (HSC) and are responsible for platelet formation. Using a mouse knockout model with normal megakaryocyte numbers but essentially devoid of LCM (MK-LCM KO), we demonstrated a pronounced increase in bone marrow HSC concurrent with endogenous mobilization and extramedullary hematopoiesis. When HSC isolated from a MK-LCM KO microenvironment were transplanted in lethally irradiated mice, the absence of LCM increased HSC in BM, blood and spleen. Severe thrombocytopenia was observed in animals with diminished LCM, although there was no change in megakaryocyte ploidy distribution. In contrast, WT HSC-generated LCM regulated a normal HSC pool and prevented thrombocytopenia. The present label-free quantitative LC-MSMS data was used to determine proteins that are differentially expressed in bone marrow cells of MK-LCM WT versus MK-LCM KO mice.
2023-05-10 | PXD040423 | Pride
Project description:Immune thrombocytopenia (ITP) is an autoimmnue bleeding disorder characterized by low platelet count. To identify susceptibility loci for disease progression of ITP, we performed this genome-wide association study using DNA pools of 200 ITP cases and 200 controsl in Han Chinese. Performing GWAS on pools of DNA samples is an effective strategy to reduce the costs of studies and pooling DNA has been shown to be an efficient method to select candidate susceptibility loci for follow-up by individual genotyping.
2016-01-12 | GSE76744 | GEO
Project description:Immune thrombocytopenia (ITP) is an acquired autoimmune disease triggered by abnormal T cell immunity, especially the impairment of regulatory T (Treg) cells and helper T (Th) cell subsets. Decitabine, a hypomethylating agent promoting cell differentiation at low dose, has been demonstrated the function of increasing the number of mature polyploidy megakaryocytes in ITP as well as Treg cells in allogeneic transplantation. Recently, our clinical study proved that decitabine was effective and safe in the management of adult ITP patients, and nearly half showed sustained responses. However, whether low-dose decitabine has the potential in restoring immune tolerance in ITP is unknown. In our in vitro studies, we identified that low-dose decitabine could promote the generation and differentiation and enhance the immunosuppressive function of Treg cells. Furthermore, low-dose decitabine alleviated thrombocytopenia and regained the balance of Treg/Th cell subsets in active murine models of ITP. For patients who received low-dose decitabine therapy and showed responses, the quantity and function of Treg cells were substantially improved, whereas Th1 and Th17 cells were depressed compared with the pretreatment levels. Finally, immunophenotyping and next-generation RNA sequencing analysis showed that low-dose decitabine restored T cell homeostasis and decreased the level of proinflammatory cytokines along with the downregulation of STAT3 and Akt in refractory ITP patients. Therefore, our data reveal the immunomodulatory effect of decitabine and provide unique insights into the sustained response achieved by decitabine in the management of ITP patients.
2020-07-21 | GSE154703 | GEO
Project description:Immune thrombocytopenia (ITP) is an autoimmune disease where platelets are destroyed prematurely. In the majority of children the disease resolves but in some it becomes chronic. To investigate whether the two forms of the disease are similar or separate entities we performed DNA microarray analysis of T-cells from newly diagnosed children and children with chronic ITP. We found complete separation of the expression files between the two forms of the disease. Furthermore, the gene expression of several cytokines differed between the two forms of the disease. This was also reflected in plasma with increased levels of IL-16 and TWEAK and lower levels of IL-4 in newly diagnosed compared with chronic ITP. Thus, our data indicate that the two forms of the disease may be separate entities. Microarray expression analysis of mRNA in peripheral blood T-cell of Newly diagnosed ITP vs Chronic ITP
2013-08-05 | E-GEOD-46922 | biostudies-arrayexpress
Project description:Physical factors can have major influences on the proliferation and differentiation fate of hematopoietic stem cells in culture. Recently, we demonstrated that cord blood CD34+ cells undergo accelerated and increased megakaryocyte differentiation when incubated at 39°C. In this study, we investigated in detail the impacts of mild hyperthermia on the kinetics of megakaryocyte differentiation, maturation, polyploidization and cell viability. The qualitative and quantitative effects on Mk differentiation were found to be rapidly induced, and optimization of the culture length at 39°C led to greater Mk yields. Mild hyperthermia did not promote endomitosis of cord blood-derived Mk, but rather led to a small reduction in the proportion of polyploid Mk. Moreover, it had little impact on viability but induced a significant shift in the proportion of cells undergoing apoptosis at 37°C to necrosis at 39°C. Finally, our results suggest that the effects on megakaryocyte differentiation could be the consequences of aberrant expression of key megakaryocyte transcription factors induced by mild hyperthermia. Experiment Overall Design: To define potential differences between megakaryocytes (Mk) derived at 37°C or 39°C, we compared their gene expression repertoire by micro-gene chip technology (Affymetrix GeneChip HG133A). Two independent experiments were carried out on Mk at 37 or 39°C. CD41a+ Mk issued from CB CD34+ cells were cultured for 7-days with TPO at 100 ng/ml and purified by positive magnetic selection using a CD41a-FITC monoclonal antibody (Immunotech, Marseille, France) and MACS columns according to manufacturerâs instructions (Miltenyi, Auburn, CA, USA) with a purity of >95%.
2008-06-16 | E-GEOD-9218 | biostudies-arrayexpress