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Publication
Journal: Molecules and Cells
February/11/2010
Abstract
Human SIRT3 gene contains an intronic VNTR enhancer. A T>> C transition occurring in the second repeat of each VNTR allele implies the presence/absence of a putative GATA binding motif. A partially overlapping AP-1 site, not affected by the transition, was also identified. Aims of the present study were: 1) to verify if GATA and AP-1 sites could bind GATA2 and c-Jun/c-Fos factors, respectively; 2) to investigate whether such sites modulate the enhancer activity of the SIRT3-VNTR alleles. DAPA assay proved that GATA2 and c-Jun/c-Fos factors are able to bind the corresponding sites. Moreover, co-transfection experiments showed that the over-expression of GATA2 and c-Jun/c-Fos factors boosts the VNTR enhancer activity in an allelic-specific way. Furthermore, we established that GATA2 and c-Jun/c-Fos act additively in modulating the SIRT3-VNTR enhancer function. Therefore, GATA2 and AP-1 are functional sites and the T S> C transition of the second VNTR repeat affects their activity.
Publication
Journal: Journal of Genetics and Genomics
April/8/2013
Abstract
Kaiso zinc finger-containing protein (Kzp), a maternally-derived transcription factor, controls dorsoventral patterning during zebrafish gastrulation. Here, we uncovered a new function for Kzp in zebrafish embryonic primitive hematopoiesis. The depletion of kzp led to defects in primitive hematopoiesis including the development of the erythroid and myeloid lineages. On the other hand, overexpression of kzp caused the ectopic expression of gata1, gata2, and pu.1. Chromosome immunoprecipitation assays revealed that Kzp protein directly binds to gata1, gata2, and pu.1 promoters. Interestingly, the ectopic expression of gata2 was able to rescue the erythroid, but not the myeloid lineage in kzp-depleted zebrafish embryos. gata1 expression controlled by Kzp was dependent on gata2 during primitive erythropoiesis. Our results indicate that Kzp is a critical transcriptional factor for the expression of gata2 and pu.1 to modulate primitive hematopoiesis.
Publication
Journal: Annals of Applied Statistics
November/13/2018
Abstract
In recent years, a large number of genomic and epigenomic studies have been focusing on the integrative analysis of multiple experimental datasets measured over a large number of observational units. The objectives of such studies include not only inferring a hidden state of activity for each unit over individual experiments, but also detecting highly associated clusters of units based on their inferred states. Although there are a number of methods tailored for specific datasets, there is currently no state-of-the-art modeling framework for this general class of problems. In this paper, we develop the MBASIC (Matrix Based Analysis for State-space Inference and Clustering) framework. MBASIC consists of two parts: state-space mapping and state-space clustering. In state-space mapping, it maps observations onto a finite state-space, representing the activation states of units across conditions. In state-space clustering, MBASIC incorporates a finite mixture model to cluster the units based on their inferred state-space profiles across all conditions. Both the state-space mapping and clustering can be simultaneously estimated through an Expectation-Maximization algorithm. MBASIC flexibly adapts to a large number of parametric distributions for the observed data, as well as the heterogeneity in replicate experiments. It allows for imposing structural assumptions on each cluster, and enables model selection using information criterion. In our data-driven simulation studies, MBASIC showed significant accuracy in recovering both the underlying state-space variables and clustering structures. We applied MBASIC to two genome research problems using large numbers of datasets from the ENCODE project. The first application grouped genes based on transcription factor occupancy profiles of their promoter regions in two different cell types. The second application focused on identifying groups of loci that are similar to a GATA2 binding site that is functional at its endogenous locus by utilizing transcription factor occupancy data and illustrated applicability of MBASIC in a wide variety of problems. In both studies, MBASIC showed higher levels of raw data fidelity than analyzing these data with a two-step approach using ENCODE results on transcription factor occupancy data.
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Publication
Journal: General and Comparative Endocrinology
August/27/2019
Abstract
Corticotropin-releasing hormone (CRH) is known to act as a potent thyrotropin-releasing factor in non-mammalian species such as chicken and bullfrog. This interaction is mediated by type 2 CRH receptors (CRHR2) expressed by the thyrotropes in the pituitary gland. However, the response elements (REs) and their corresponding transcription factors (TFs) that control CRHR2 expression in thyrotropes are not known. Since thyrotrope-specific expression of the β-subunit of thyrotropin is synergistically stimulated by the co-expression of POU1F1 and GATA2, we hypothesised that in non-mammalian vertebrates like chicken, CRHR2 expression is controlled by the same TFs and that their REs are present in the chicken CRHR2 gene promoter. In situ hybridisation and immunohistochemistry suggest that chicken thyrotropes, like those of mammals, express the mRNAs for the TFs GATA2, POU1F1 and PITX1, but not NR5A1. Using luciferase reporter assays, we show that both GATA2 and PITX1 can activate the promoter of CRHR2, but PITX1 requires a functional GATA2 RE to be present. POU1F1 alone did not affect promoter activity, but synergistically increased the effect of GATA2. Promoter deletion analysis and mutagenesis showed that essential GATA2 and PITX1 REs are located between 116 and 198 bp upstream of the start codon. These REs are highly conserved in non-mammalian species. Additionally, NR5A1 (steroidogenic factor 1) suppressed both GATA2- and PITX1-induced promoter activity and may therefore play a role in restricting CRHR2 expression in gonadotropes. We conclude that the expression of CRHR2 in chicken thyrotropes is stimulated by GATA2 with interactions with POU1F1 and PITX1, in the absence of NR5A1.
Publication
Journal: Journal of Maternal-Fetal and Neonatal Medicine
February/22/2021
Abstract
Aim: Gestational diabetes mellitus is common during pregnancy, impacting maternal health and fetal development. The aim of this study was to identify potential long non-coding RNAs (lncRNAs) and mRNAs in gestational diabetes mellitus.
Methods: The placenta tissues from four women patients with gestational diabetes mellitus and three healthy pregnant women were used for RNA sequencing. Differentially expressed lncRNAs and mRNAs were obtained. Then, interaction networks of lncRNA-nearby targeted mRNA and lncRNA-co-expressed mRNA were constructed, followed by functional annotation of co-expressed mRNAs. Third, GSE51546 dataset was utilized to validate the expression of selected co-expressed mRNAs. In addition, in vitro experiment was applied to expression validation of lncRNAs and mRNAs. Finally, GSE70493 dataset was utilized for diagnostic analysis of selected co-expressed mRNAs.
Results: A total of 78 differentially expressed lncRNAs and 647 differentially expressed mRNAs in gestational diabetes mellitus were obtained. Several interaction pairs of lncRNA-co-expressed mRNA including LINC01504-CASP8, FUT8-AS1-TLR5/GDF15, GATA2-AS1-PQLC3/KIAA2026, and EGFR-AS1-HLA-G were identified. Endocytosis (involved HLA-G) and toll-like receptor signaling pathway (involved TLR5 and CASP8) were remarkably enriched signaling pathways of co-expressed mRNAs. It is noted that CASP8, TLR5, and PQLC3 had a significant prognosis value for gestational diabetes mellitus.
Conclusions: Our study identified several differentially expressed lncRNAs and mRNAs, and their interactions, especially co-expression, may be associated with gestational diabetes mellitus.
Keywords: Gestational diabetes mellitus; endocytosis; lncRNAs; mRNAs; toll-like receptor.
Publication
Journal: Global Pediatric Health
November/12/2018
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Publication
Journal: Indian Journal of Pediatrics
January/14/2020
Publication
Journal: Nan fang yi ke da xue xue bao = Journal of Southern Medical University
January/10/2010
Abstract
OBJECTIVE
To characterize the time course of spontaneous differentiation of in vitro cultured human embryonic stem cells (hESCs) into hematopoietic cells to provide experimental evidence for induction of hematopoietic commitment of hESCs.
METHODS
In human embryoid bodies (hEBs) derived from spontaneous differentiation of chESC3, a hESC cell line we established previously, the expressions of such genes as KDR, Bmi1, Scl and gata2 were detected by RT-PCR every other day during the 12-day differentiation to monitor the process of the hematopoiesis. The hematopoietic stem cell marker CD34 was examined using flow cytometry to evaluate the efficiency of hematopoietic differentiation of the cells on days 6, 8, 10 and 12. The spontaneously differentiated hESCs were seeded in the hematopoietic colony culture system to study the hematopoietic colony forming ability. Immunocytochemical staining for CD45 was performed on the hEBs to examine the emergence of mature hematopoietic cells.
RESULTS
The expressions of the hematopoietic stem cell-related genes KDR and Bmi-1 were detected in the hESCs, and on days 4 to 6, the two genes were upregulated with prolonged cuture of the hEBs. Scl and gata2 gene expressions were detected since 6-8 days of culture and maintained high expressions till day 12. Flow cytometry revealed a gradual increase in CD34-positive cells in the culture, with positivity rates on days 6, 8, 10, and 12 of (1.4-/+0.4)%, (3.4-/+1.3)%, (5.5-/+2.2)%, and (5.1-/+1.7)%, respectively. The numbers of CD43-positive cell colonies on days 6, 8, 10, and 12 were 0, 7-/+2, 37-/+11, and 89-/+29 in each 10(5) cells, respectively. Immunocytochemical staining identified CD45-positive cells on days 10, 12, 15, and 18 in the cell colonies, with the positive cell numbers of 0, 40.5-/+15.09, 178.6-/+55.89, and 253.0-/+52.04, respectively.
CONCLUSIONS
The hESCs undergo spontaneous hematopoietic differentiation in 3 stages, including the differentiation into germ layer-specific cells (days 6-8), expansion period of the hematopoitic progenitors (days 8-12), and maturation of the hematopoietic cells (after day 15).
Publication
Journal: Zhonghua xue ye xue za zhi = Zhonghua xueyexue zazhi
October/28/2018
Abstract
Objective: To explore the role of PDK1 in the transition of endothelial to hematopoietic cells and its effect on the generation and normal function of HSC. Methods: PDK1 was deleted specifically in endothelial cells expressing VEC (Vascular Endothelial Cadherin). CFU-C was performed to detect the effect of PDK1 on the function of hematopoietic progenitor cells using the cells from PDK1(fl/fl), PDK1(fl/+) and Vec-Cre; PDK1(fl/fl) AGM region. Hematopoietic stem cell transplantation assay was conducted to determine the effect of PDK1 on hematopoietic stem cells. Flow cytometry was performed to analyze the influence of PDK1 on percentage, cell cycle and apoptosis of CD31(+)c-Kit(high) cell population. Real-time PCR was conducted to measure the expression of transcription factors involved in process of transition from endothelial to hematopoietic cells. Results: In contrast to the wild type group, the CFU from PDK1-deficient hematopoietic progenitor cells showed smaller in morphology and fewer in quantity. CFU-GM was (24±5)/ee in knockout group, and the control group was (62±1)/ee (P=0.001). PDK1 deletion severely impaired the ability to repopulate hematopoietic cells and differentiate into committed cells. hematopoietic progenitor cells from knockout group was transplanted into 5 recipients without any recipients reconstructed. However, 5 of 7 recipients were reconstructed in control group (P=0.001). The proportion of intra-vascular clusters in the AGM was decreased (the frequency of CD31(+)c-Kit(high) in the knockout group was (0.145±0.017)%, and the control group ratio was (0.385±0.040)% (P=0.001), but not due to the inhibition of cell proliferation and/or increase of apoptosis. Further study found that the absence of endothelial PDK1 causes a decreased expression of RUNX1, P2-RUNX1, GATA2 and other important hematopoietic-related transcription factors in hemogenic cluster. Conclusion: PDK1 deletion impairs the transition of endothelial cells to hematopoietic cells as well as the generation and function of HSC.
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Publication
Journal: Immunology and Cell Biology
October/21/2018
Abstract
Myeloid-derived suppressor cells (MDSCs) represent a group of immature myeloid cells composed of myeloid progenitor cells and immature myeloid cells that can negatively regulate immune responses by inhibiting T-cell function. In mice, MDSCs are broadly defined by the expression of CD11b and Gr1. We and others have shown that injection of a lethal or sublethal dose of lipopolysaccharide (LPS) into mice could result in the expansion of MDSCs in the bone marrow (BM), spleen and blood. Until now, the molecular mechanisms responsible for this expansion are poorly studied; specifically, the roles of the individual microRNAs (miRNAs) which may be involved remain largely unknown. We performed microarray analysis to compare the miRNA expression profiles of CD11b+ Gr1+ cells sorted from the BM of LPS-injected and phosphate-buffered saline-injected mice. We identified let-7e, which was highly upregulated in the LPS-treated group, as a potent regulator of LPS-induced MDSC expansion. Furthermore, let-7e overexpression in BM chimeric mice led to a noticeable increase in the population of CD11b+ Gr1+ cells, which resulted from reduced cellular apoptosis. Further studies showed that let-7e could directly target caspase-3 to inhibit cell apoptosis, and upregulation of let-7e in LPS-stimulated MDSCs could be due to the relieved repression of let-7e transcription exerted by downregulated GATA2. Our findings suggest that LPS expands MDSCs by inhibiting apoptosis through the regulation of the GATA2/let-7e axis.
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Publication
Journal: Genes
April/2/2019
Abstract
Hematopoietic cells are continuously replenished from progenitor cells that reside in the bone marrow. To evaluate molecular changes during this process, we analyzed the transcriptomes of freshly harvested human bone marrow progenitor (lineage-negative) and differentiated (lineage-positive) cells by single-molecule real-time (SMRT) full-length RNA-sequencing. This analysis revealed a ~5-fold higher number of transcript isoforms than previously detected and showed a distinct composition of individual transcript isoforms characteristic for bone marrow subpopulations. A detailed analysis of messenger RNA (mRNA) isoforms transcribed from the ANXA1 and EEF1A1 loci confirmed their distinct composition. The expression of proteins predicted from the transcriptome analysis was evaluated by mass spectrometry and validated previously unknown protein isoforms predicted e.g., for EEF1A1. These protein isoforms distinguished the lineage negative cell population from the lineage positive cell population. Finally, transcript isoforms expressed from paralogous gene loci (e.g., CFD, GATA2, HLA-A, B, and C) also distinguished cell subpopulations but were only detectable by full-length RNA sequencing. Thus, qualitatively distinct transcript isoforms from individual genomic loci separate bone marrow cell subpopulations indicating complex transcriptional regulation and protein isoform generation during hematopoiesis.
Publication
Journal: Experimental Hematology
November/19/2017
Abstract
The bone marrow (BM) microenvironment comprises multiple stem cell niches derived from BM mesenchymal stem cells (MSCs). Previous in vitro analyses have suggested that transcription factor GATA2 plays an important role in adipocyte differentiation of BM-MSCs and in hematopoietic support, but the role of GATA2 in vivo remains unknown. We evaluated GATA2 effects in BM-MSCs in vivo. Expression profiling analysis of Gata2-knockout Ter119-CD45- mesenchymal stromal cells obtained from compact bone from tamoxifen-treated Gata2 conditional knockout mice (Gata2f/f/ER-Cre mice) revealed upregulation of 110 genes and downregulation of 141 genes by a factor of 2. Moreover, gene ontology analysis revealed significant enrichment of genes involved in cell adhesion and chemotaxis. We did not find any phenotypic changes when Gata2 was deleted with BM-MSC-related gene promoters, such as Nestin, Prx1, and Lepr, except for a significant decrease in the colony number of Gata2f/f/Prx1-Cre mice. There was a significant decrease in the percentage of the common myeloid progenitor fraction when Gata2 was deleted in all BM cells, except hematopoietic cells after normal BM cells were transplanted into irradiated Gata2f/f/ER-Cre mice with Gata2 subsequently knocked out by tamoxifen administration. In conclusion, GATA2 could affect the function of BM-MSCs in vivo, presumably by regulating the expression of extracellular signals.
Publication
Journal: Experimental Hematology
September/5/2016
Abstract
Transforming growth factor β (TGFβ) is a potent inhibitor of hematopoietic stem and progenitor cell proliferation. However, the precise mechanism for this effect is unknown. Here, we have identified the transcription factor Gata2, previously described as an important regulator of hematopoietic stem cell function, as an early and direct target gene for TGFβ-induced Smad signaling in hematopoietic progenitor cells. We also report that Gata2 is involved in mediating a significant part of the TGFβ response in primitive hematopoietic cells. Interestingly, the cell cycle regulator and TGFβ signaling effector molecule p57 was found to be upregulated as a secondary response to TGFβ. We observed Gata2 binding upstream of the p57 genomic locus, and importantly, loss of Gata2 abolished TGFβ-stimulated induction of p57 as well as the resulting growth arrest of hematopoietic progenitors. Our results connect key molecules involved in hematopoietic stem cell self-renewal and reveal a functionally relevant network, regulating proliferation of primitive hematopoietic cells.
Publication
Journal: Zhonghua xue ye xue za zhi = Zhonghua xueyexue zazhi
July/25/2019
Abstract
Objective: To clarify the prevalence, clinical features and molecular characteristics of germline GATA2 mutations in pediatric primary myelodysplastic syndromes (MDS) . Methods: Next-generation sequencing technology was used to detect mutations in GATA2 and other myeloid malignancy genes in 129 children with primary MDS from Jan. 2007 to Jan. 2018. The relationship between genotypes and phenotypes was analyzed. Results: Germline GATA2 mutations accounted for 8.5% (11/129) of all primary MDS cases, and 14.0% (11/50) of MDS with excess blasts (MDS-EB) and acute myeloid leukaemia with myelodysplasia-related changes (AML-MRC) . Compared with GATA2 wild-type patients, GATA2 mutated patients were older at diagnosis[8 (1-16) years old vs 6 years old (range: 1 month old-18 years old) , P=0.035]and higher risk of monosomy 7 (72.7%vs 5.2%, P<0.001) and classified into MDS-EB and AML-MRC compared with refractory cytopenia of childhood (RCC) (63.6%vs 36.4%, P=0.111) . The multivariate analysis showed SETBP1 mutation (P=0.041, OR=9.003, 95%CI 1.098-73.787) and isolated monosomy 7 (P=0.002, OR=24.835, 95%CI 3.305-186.620) were significantly associated with germline mutated GATA2. Overall survival (OS) and outcomes of hematopoietic stem cell transplantation (HSCT) were not influenced by GATA2 mutational status. Conclusions: Our data identify germline GATA2 mutations have a high prevalence in older pediatric patients with monosomy 7, and high risk of progression into advanced MDS subtypes. GATA2 mutation status does not affect OS in pediatric primary MDS.
Authors
Publication
Journal: Blood advances
December/12/2018
Abstract
GATA2 deficiency is an inherited or sporadic genetic disorder characterized by distinct cellular deficiency, bone marrow failure, various infections, lymphedema, pulmonary alveolar proteinosis, and predisposition to myeloid malignancies resulting from heterozygous loss-of-function mutations in the GATA2 gene. How heterozygous GATA2 mutations affect human hematopoietic development or cause characteristic cellular deficiency and eventual hypoplastic myelodysplastic syndrome or leukemia is not fully understood. We used induced pluripotent stem cells (iPSCs) to study hematopoietic development in the setting of GATA2 deficiency. We performed hematopoietic differentiation using iPSC derived from patients with GATA2 deficiency and examined their ability to commit to mesoderm, hemogenic endothelial precursors (HEPs), hematopoietic stem progenitor cells, and natural killer (NK) cells. Patient-derived iPSC, either derived from fibroblasts/marrow stromal cells or peripheral blood mononuclear cells, did not show significant defects in committing to mesoderm, HEP, hematopoietic stem progenitor, or NK cells. However, HEP derived from GATA2-mutant iPSC showed impaired maturation toward hematopoietic lineages. Hematopoietic differentiation was nearly abolished from homozygous GATA2 knockout (KO) iPSC lines and markedly reduced in heterozygous KO lines compared with isogenic controls. On the other hand, correction of the mutated GATA2 allele in patient-specific iPSC did not alter hematopoietic development consistently in our model. GATA2 deficiency usually manifests within the first decade of life. Newborn and infant hematopoiesis appears to be grossly intact; therefore, our iPSC model indeed may resemble the disease phenotype, suggesting that other genetic, epigenetic, or environmental factors may contribute to bone marrow failure in these patients following birth. However, heterogeneity of PSC-based models and limitations of in vitro differentiation protocol may limit the possibility to detect subtle cellular phenotypes.
Publication
Journal: Journal of Pediatric Hematology/Oncology
July/24/2018
Abstract
Emberger syndrome with underlying guanine-adenine-thymine-adenine 2 (GATA2) mutation is a rare disorder and very few successful nonmyeloablative allogeneic hematopoietic stem cell transplants (HSCTs) have been reported. We report a case of Emberger syndrome with GATA2 mutation in a 9-year-old girl who presented with congenital sensorineural deafness, warts, lymphedema, and Myelodysplastic syndrome. Her sister had died of a similar illness. She underwent a nonmyeloablative matched related donor peripheral blood HSCT with rabbit antithymoglobulin (5 mg/kg), fludarabine (160 mg/m), cyclophophamide (29 mg/kg), and total body irradiation (2 Gray). Graft versus host disease prophylaxis consisted of tacrolimus and mycophenolate moefetil. She had neutrophil engraftment on day+15 and fully donor chimerism by day+30. She developed limited chronic skin graft versus host disease on tapering off immunosuppression. She is disease free on day+475. The review of literature showed a total of 28 patients with GATA2 mutation have undergone HSCT mostly nonmyeloablative and overall survival is 75%. Nonmyeloablatove HSCT is feasible and safe for the patients with GATA2 mutation.
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Publication
Journal: Animal Science Journal
April/5/2015
Abstract
In vertebrates, six GATA transcription factors, GATA1 through GATA6, have been identified and GATA1-3 is known to be involved in hematopoietic developments, while GATA4-6 play roles in cardiac and endoderm developments. Recently, we and others have found that GATA2 and GATA3 found in the trophectoderm plays a role in gene expression specific to this cell type, but GATA4-6 have not been well characterized in early embryonic developments. Using quantitative polymerase chain reaction (qPCR) and in situ hybridization, we examined the expression of GATA4, 5 and 6 messenger RNAs (mRNAs) in ovine conceptuses and uteri during the peri-implantation period. In ovine conceptuses, GATA4, 5 and 6 transcripts were present on days 15, 17 and 21 (day 0 = day of mating), and high GATA5 and 6 mRNAs were found on day 21, most of which were localized in the trophectoderm and endoderm. Moreover, minute and substantial GATA4 and 5 mRNAs were found in days 15 and 21 uterine endometria, respectively. Increase in GATA4-6 transcripts in day 21 uteri indicates that in addition to GATA1-3, GATA4-6 may also play a potentially novel role in the development of ovine trophectoderm, endoderm and/or uterine endometria following conceptus attachment to the uterine epithelium.
Publication
Journal: Stem Cells
December/11/2018
Abstract
Previously, we reported that although the HSPC frequency in bone marrow cells (BMC) was comparable between β2-/- and β2+/+ mice, transplantation of β2-/- BMC into lethally irradiated CD45.1 recipient resulted in more myeloid cell production than β2+/+ BMC. The objective of this study is to address if integrin β2 deficiency skews granulocyte/macrophage progenitor (GMP) proliferation. FACS analysis demonstrated that GMP frequency and cell number were higher and megakaryocyte/erythrocyte progenitor frequency and cell number were lower in β2-/- mice than β2+/+ mice. However, the common myeloid progenitors (CMP) frequency and cell number were similar between the two groups. The increased GMP number was due to GMP proliferation as evidenced by the percentage of BrdU-incorporating GMP. Whole genome transcriptome analysis identified increased FcεRIα expression in β2-/- CMP compared to β2+/+ CMP. FcεRIα expression on β2-/- GMP was detected increased in β2-/- mice by qRT-PCR and FACS. Although transplantation of FcεRIαhi GMP or FcεRIαlo GMP into lethally irradiated CD45.1 recipient resulted in comparable myeloid cell production, transplantation of β2 deficient FcεRIαhi GMP generated more myeloid cells than β2+/+ FcεRIαhi GMP. GATA2 expression was increased in β2-/- GMP. Using a luciferase reporter assay, we demonstrated that mutation of the GATA2 binding site in the FcεRIα promoter region diminished FcεRIα transcription. In vitro, the addition of IgE, the ligand of FcεRIα, promoted GMP expansion, which was abrogated by inhibition of JNK phosphorylation. Integrin β2 deficiency promoted GMP proliferation and myeloid cell production, which was mediated via FcεRIα/IgE-induced JNK phosphorylation in GMP. Stem Cells 2019;37:430-440.
Publication
Journal: Advanced Pharmaceutical Bulletin
May/6/2020
Abstract
Purpose: Mesenchymal stem cells (MSCs) release hematopoietic cytokines, growth factors, and Microvesicles (MVs) supporting the hematopoietic stem cells (HSCs). MVs released from various cells, playing a crucial role in biological functions of their parental cells. MSC-derived MVs contain microRNAs and proteins with key roles in the regulation of hematopoiesis. Umbilical cord blood (UCB) is a source for transplantation but the long-term recovery of platelets is a main problem. Therefore, we intend to show that MSC-MVs are able to improve the differentiation of UCB-derived CD34+ cells to megakaryocyte lineage. Methods: In this descriptive study, MSCs were cultured in DMEM to collect the culture supernatant, which was ultracentrifuged for the isolation of MVs. HSCs were isolated from UCB using MACS method and cultured in IMDM supplemented with cytokines and MVs in three different conditions. Megakaryocyte differentiation was evaluated through the expression of specific markers and genes after 72 hours, and the data was analyzed by t test (P<0.05). Results: The expression of specific megakaryocyte markers (CD41 and CD61) in the presence of different concentrations of MSC-MVs did not show any significant difference. Also, the expression of specific genes of megakaryocyte lineage was compared with control group. The expression of GATA2 and c-Mpl was significantly increased, GATA1 was not significantly decreased, and FLI1 was significantly decreased. Conclusion: MSC-MVs could improve the expression of specific megakaryocyte genes; however, there was no significant expression of CD markers. Further studies, including the evaluation of late stages of megakaryocyte differentiation, are required to evaluate platelet production and shedding.
Publication
Journal: Pediatric Blood and Cancer
June/12/2017
Publication
Journal: Journal of Immunology
October/31/2017
Abstract
The neurobeachin-like 2 protein (Nbeal2) belongs to the family of beige and Chediak-Higashi (BEACH) domain proteins. Loss-of-function mutations in the human NBEAL2 gene or Nbeal2 deficiency in mice cause gray platelet syndrome, a bleeding disorder characterized by macrothrombocytopenia, splenomegaly, and paucity of α-granules in megakaryocytes and platelets. We found that in mast cells, Nbeal2 regulates the activation of the Shp1-STAT5 signaling axis and the composition of the c-Kit/STAT signalosome. Furthermore, Nbeal2 mediates granule formation and restricts the expression of the transcription factors, IRF8, GATA2, and MITF as well as of the cell-cycle inhibitor p27, which are essential for mast cell differentiation, proliferation, and cytokine production. These data demonstrate the relevance of Nbeal2 in mast cells above and beyond granule biosynthesis.
Publication
Journal: Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology
August/17/2020
Abstract
Objective: To analyze the effect of clinical features, routine laboratory examination and related gene mutation on the OS of patients with myelodysplastic syndrome (MDS) after hematopoietic stem cell transplantation (HSCT).
Methods: 121 patients diagnosed as MDS and underwent hematopoietic stem cell transplantation in the First Affiliated Hospital of Soochow University from October 2013 to August 2018 were selected. Basic information of the patients was collected, and blood cells, bone marrow blasts at initial diagnosis, chromosomal karyotypes and gene mutations of the patients were detected.The effect of different factors on overall survival (OS) was analyzed by statistical method.
Results: Kaplan-Meier univariate analysis shows that OS was significanly different among different age groups. The 3-year OS rate of patients aged 0-29 years was (83.3±7.7) %, the 3-year OS rate in patients aged 30-49 years was (58.1±7.7 %), and the 3-year OS rate of patients aged 50-69 years was (31.0±22.6) %, which was statistically different (P<0.05) between different groups. There were also significant differences in OS among patients with different transplantation types. 3-year OS rate: HLA-matched sibling HSCT>unrelated HLA-matched HSCT>haploidentical HSCT>micro HSCT. The OS rate of patients with bone marrow blasts≥10% seems lower than blasts<10%, but there was no statistical difference.The 3-year OS rate of patients with chromosomal karyotype complex abnormality was (47.7±11.5) %, and that of patients without complex abnormality was (80±4.2) % which was statistical difference (P<0.05). Patients with DNMT3A, NRAS, TP53 and GATA2 mutations had shorter OS time compared with patients without mutation of these genes, which shows statistically significant (P<0.05). COX multivariate analysis showed that age, chromosome karyotype, DNMT3A, TET2, GATA2 and NRAS were the independent factors influencing OS of patients after HSCT, with statistically significant difference.
Conclusion: age of patients, donor selection of HSCT, chromosome karyotype, DNMT3A, NRAS, TP53, GATA2 and TET2 gene mutations are all independent factors affecting the OS of patients after HSCT. Therefore, the assessment of the OS of MDS patients with transplantation requires comprehensive consideration.
题目: 影响造血干细胞移植的骨髓增生异常综合征患者 生存期的因素分析.
目的: 分析进行造血干细胞移植的骨髓增生异常综合征(myelodysplastic syndrome,MDS)患者的临床特点、常规实验室检查及相关基因突变对总生存期(overall survival,OS)的影响.
方法: 选取并回顾性分析2013年10月至2018年8月在苏州大学附属第一医院诊断MDS并进行造血干细胞移植(hematopoietic stem cell transplantation,HSCT)的患者121例,收集患者基本信息,并检测患者血细胞、初诊骨髓原始细胞、染色体核型及基因突变情况。用统计学方法分析不同因素对生存期的影响.
结果: Kaplan-Meier单因素分析发现,不同年龄段之间OS有明显差异,患者年龄越高,3年OS率越低,0-29岁患者3年OS率为(83.3±7.7)% ;30-49岁患者3年OS率为(58.1±7.7)%;50-69岁患者均3年OS率为(31.0±22.6)%, 且各组之间OS率统计学差异显著(P<0.05)。不同移植类型对患者OS也有显著影响,3年OS率:同胞全相合HSCT>非血缘全相合HSCT>单倍体相合HSCT>微移植。骨髓原始细胞≥10%的患者OS率低于<10%的患者,但差异没有统计学意义。染色体核型复杂异常患者3年OS率为(47.7±11.5)%,非复杂异常患者的3年OS率为(80±4.2)%(P<0.05)。DNMT3A、NRAS、TP53、GATA2基因非突变患者比基因突变的患者移植后OS期长,差异有统计学意义(P<0.05)。COX多因素分析结果显示,年龄、染色体核型、DNMT3A、TET2、GATA2、NRAS对MDS移植后OS有独立影响,且差异具有统计学意义.
结论: 患者年龄,造血干细胞移植供体选择,患者初诊染色体核型,DNMT3A、NRAS、TP53、GATA2、TET2基因突变均是影响MDS移植后生存期的独立因素。因此对MDS移植患者生存期的评估需要综合多方面考虑.
Publication
Journal: Developmental and Comparative Immunology
November/13/2013
Abstract
The development of macrophages is a highly regulated process requiring coordination amongst transcription factors. The presence/absence, relative levels, antagonism, or synergy of all transcription factors involved is critical to directing lineage cell fate and differentiation. While relative levels of many key myeloid transcription factors have been determined in mammalian macrophage differentiation, a similar set of studies have yet to be conducted in a teleost system. In this study, we report on the mRNA levels of transcription factors (cebpa, cjun, cmyb, egr1, gata1, gata2, gata3, lmo2, mafb, pax5, pu.1 and runx1) in sorted goldfish progenitor cells, monocytes, and macrophages from primary kidney macrophage cultures. The mRNA levels of runx1 and pu.1 were significantly higher, gata3 and pax5 mRNA levels were lower, in monocytes compared to progenitors, and the mRNA levels of cjun, egr1, gata2, gata3, mafb and pax5 were significantly decreased in macrophages compared to progenitor cells. The relative mRNA levels of the interferon regulatory factor family of transcription factors, irf1, irf2, irf5, irf7, irf8 and irf9 in sorted progenitors, monocytes and macrophages were also measured. In contrast to other irf family transcription factors examined, irf8 mRNA levels were increased in monocytes compared to progenitors by greater than three-fold, suggesting that irf8 is important for monopoiesis. Lastly, we show the differential regulation of myeloid transcription factor mRNA levels in sorted progenitor cells from 1, 2, or 3-day old cultures in response to the recombinant goldfish growth factors, rgCSF-1 and rgKITLA.
Publication
Journal: Pediatric Research
April/28/2010
Abstract
We describe a patient, who developed during the first week of life petechiae and hematomas caused by severe thrombocytopenia and gastrointestinal bleeding due to multiple small gastric hemangiomata. Bone marrow examination showed hypermegakaryocytosis and dysmegakaryopoiesis. Alloimmune thrombocytopenia was excluded. Only 3 y later, platelet counts normalized and bleedings disappeared but small skin hemangiomata remained. Electron microscopy showed enlarged round platelets with a paucity of alpha granules similar as in GATA1-deficient patients but no GATA1 mutation was found. Immunoblot analysis showed a strong interaction between patient Igs and recombinant GATA1, GATA2, and the N finger (Nf) of GATA1. The lymphocyte transformation test with recombinant GATA1Nf was positive. In vitro culturing of normal CD34 cells with purified patient Igs showed a decreased number of megakaryocyte colonies but an increased overall size of the colonies compared with control Igs. Mice injected with patient Igs showed a reduced platelet count compared with mice injected with control Igs. Thrombopoiesis was also reduced after injection of patient Igs in transgenic zebrafish compared with control Igs. In conclusion, this study is the first report of an anti-GATA1 autoantibody leading to severe thrombocytopenia and gastrointestinal bleeding from multiple pinpoint hemangiomata.
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