搜索结果: 'methocult media formulations for human hematopoietic cells serum containing'

MicroRNAs (miRNAs) are pivotal for regulation of hematopoiesis but their critical targets remain largely unknown. Here,we show that ectopic expression of miR-17,-20,-93 and -106,all AAAGUGC seed-containing miRNAs,increases proliferation,colony outgrowth and replating capacity of myeloid progenitors and results in enhanced P-ERK levels. We found that these miRNAs are endogenously and abundantly expressed in myeloid progenitors and down-regulated in mature neutrophils. Quantitative proteomics identified sequestosome 1 (SQSTM1),an ubiquitin-binding protein and regulator of autophagy-mediated protein degradation,as a major target for these miRNAs in myeloid progenitors. In addition,we found increased expression of Sqstm1 transcripts during CSF3-induced neutrophil differentiation of 32D-CSF3R cells and an inverse correlation of SQSTM1 protein levels and miR-106 expression in AML samples. ShRNA-mediated silencing of Sqstm1 phenocopied the effects of ectopic miR-17/20/93/106 expression in hematopoietic progenitors in vitro and in mice. Further,SQSTM1 binds to the ligand-activated colony-stimulating factor 3 receptor (CSF3R) mainly in the late endosomal compartment,but not in LC3 positive autophagosomes. SQSTM1 regulates CSF3R stability and ligand-induced mitogen-activated protein kinase signaling. We demonstrate that AAAGUGC seed-containing miRNAs promote cell expansion,replating capacity and signaling in hematopoietic cells by interference with SQSTM1-regulated pathways. View Publication

The fast-growing biopharmaceutical industry demands speedy development of highly efficient and reliable production systems to meet the increasing requirement for drug supplies. The generation of production cell lines has traditionally involved manual operations that are labor-intensive,low-throughput and vulnerable to human errors. We report here an integrated high-throughput and automated platform for development of manufacturing cell lines for the production of protein therapeutics. The combination of BD FACS Aria Cell Sorter,CloneSelect Imager and TECAN Freedom EVO liquid handling system has enabled a high-throughput and more efficient cell line development process. In this operation,production host cells are first transfected with an expression vector carrying the gene of interest (1),followed by the treatment with a selection agent. The stably-transfected cells are then stained with fluorescence-labeled anti-human IgG antibody,and are subsequently subject to flow cytometry analysis (2-4). Highly productive cells are selected based on fluorescence intensity and are isolated by single-cell sorting on a BD FACSAria. Colony formation from single-cell stage was detected microscopically and a series of time-laps digital images are taken by CloneSelect Imager for the documentation of cell line history. After single clones have formed,these clones were screened for productivity by ELISA performed on a TECAN Freedom EVO liquid handling system. Approximately 2,000 - 10,000 clones can be screened per operation cycle with the current system setup. This integrated approach has been used to generate high producing Chinese hamster ovary (CHO) cell lines for the production of therapeutic monoclonal antibody (mAb) as well as their fusion proteins. With the aid of different types of detecting probes,the method can be used for developing other protein therapeutics or be applied to other production host systems. Comparing to the traditional manual procedure,this automated platform demonstrated advantages of significantly increased capacity,ensured clonality,traceability in cell line history with electronic documentation and much reduced opportunity in operator error. View Publication

Spaceflight and microgravity environments have been shown to cause significant health impairments,including bone loss,immune dysfunction,and hematopoietic disorders. Hematopoietic stem cells (HSCs),as progenitors of the hematopoietic system,are critical for the continuous renewal and regulation of immune cells. Therefore,elucidating the regulatory mechanisms governing HSC fate and differentiation in microgravity environments is of paramount importance. In this study,hindlimb unloading (HU) was employed in mice to simulate microgravity conditions. After 28 days of HU,cells were isolated for analysis. Flow cytometry and colony-forming assays were utilized to assess changes in HSC proliferation and differentiation. Additionally,transcriptomic and untargeted metabolomic sequencing were performed to elucidate alterations in the metabolic pathways of the bone marrow microenvironment and their molecular regulatory effects on HSCs fate. Our findings revealed that 28 days of HU impaired hematopoietic function,leading to multi-organ damage and hematological disorders. The simulated microgravity environment significantly increased the HSCs population in the bone marrow,particularly within the long-term and short-term subtypes,while severely compromising the differentiation capacity of hematopoietic stem/progenitor cells. Transcriptomic analysis of HSCs,combined with metabolomic profiling of bone marrow supernatants,identified 1,631 differentially expressed genes and 58 metabolites with altered abundance. Gene set enrichment analysis indicated that HU suppressed key pathways,including hematopoietic cell lineage and MAPK signaling. Furthermore,integrated analyses revealed that metabolites affected by HU,particularly hypoxanthine enriched in the purine metabolism pathway,were closely associated with hematopoietic cell lineage and MAPK signaling pathways. Molecular docking simulations and in vitro experiments confirmed that hypoxanthine interacts directly with core molecules within these pathways,influencing their expression. These findings demonstrate that hypoxanthine in the bone marrow supernatant acts as a signaling mediator under microgravity,influencing HSCs fate by modulating hematopoietic cell lineage and MAPK signaling pathways. This study offers novel insights into the impact of microgravity on HSC fate and gene expression,underscoring the pivotal role of bone marrow microenvironmental metabolic changes in regulating key signaling pathways that determine hematopoietic destiny. The online version contains supplementary material available at 10.1186/s13287-025-04213-9. View Publication

Ectopic expression of CAAT/enhancer binding protein α (C/EBPα) in p210BCR/ABL-expressing cells induces granulocytic differentiation,inhibits proliferation,and suppresses leukemogenesis. To dissect the molecular mechanisms underlying these biological effects,C/EBPα-regulated genes were identified by microarray analysis in 32D-p210BCR/ABL cells. One of the genes whose expression was activated by C/EBPα in a DNA binding-dependent manner in BCR/ABL-expressing cells is the transcriptional repressor Gfi-1. We show here that C/EBPα interacts with a functional C/EBP binding site in the Gfi-1 5'-flanking region and enhances the promoter activity of Gfi-1. Moreover,in K562 cells,RNA interference-mediated downregulation of Gfi-1 expression partially rescued the proliferation-inhibitory but not the differentiation-inducing effect of C/EBPα. Ectopic expression of wild-type Gfi-1,but not of a transcriptional repressor mutant (Gfi-1P2A),inhibited proliferation and markedly suppressed colony formation but did not induce granulocytic differentiation of BCR/ABL-expressing cells. By contrast,Gfi-1 short hairpin RNA-tranduced CD34(+) chronic myeloid leukemia cells were markedly more clonogenic than the scramble-transduced counterpart. Together,these studies indicate that Gfi-1 is a direct target of C/EBPα required for its proliferation and survival-inhibitory effects in BCR/ABL-expressing cells. View Publication

Drug resistance and relapse are still major challenges in acute myeloid leukemia (AML) because of the inability to effectively eradicate leukemia stem cells (LSCs). Senescence induction combined with immune killing may offer promising strategies for LSC eradication. However,whether and how drug-resistant LSCs retain stemness via senescence and immune regulation remains unknown. The immunoproteasome subunit PSMB10 expression levels were analyzed by single-cell RNA-seq data,along with the bioinformatics analysis of publicly available AML datasets,and quantified using RT-qPCR and flow cytometry (FCM) analysis on clinical samples from AML patients. The cellular senescence was evaluated by the assays of cell proliferation,cell cycle,senescence-associated β-galactosidase activity,and senescence-associated secretory phenotype factors. In vitro T-cell killing assay was played to determine immune escape reprogramming of AML cells. FCM was conducted to estimate intracellular drug concentration and cellular apoptosis rates. Human AML xenografts and PSMB10 knockout syngeneic mouse bone marrow transplantation models were utilized to investigate the function of PSMB10. Various techniques were employed for mechanism studies,including Lentivirus transduction or siRNA transfection,western blotting,co-immunoprecipitation assays,luciferase reporter assays,polysome profiling assays,quantitative proteomics,etc. PSMB10 mRNA was significantly upregulated in the surviving nonsenescent LSCs,exhibiting a 13-fold increase compared to senescent LSCs following chemotherapy. The specific high expression of PSMB10 in post-chemotherapy nonsenescent LSCs predicts a poor AML prognosis. The genetic inactivation of PSMB10 resulted in increased senescence and cytotoxic T lymphocyte (CTL) killing,as well as increased intracellular drug concentrations and drug-induced cellular senescence in different types of human AML cells,which also impeded human and murine leukemia initiation and stemness maintenance in vivo with a 19-fold decrease in the frequency of human LSCs and a 7.6-fold decrease of drug-resistant mouse LSCs,while normal hematopoietic cells remained unaffected. Mechanistically,the downregulation of PSMB10 boosted SLC22A16-mediated drug endocytosis and further induced chemotherapy drug-mediated senescence through the RPL6/RPS6-MDM2-P21 pathway in AML cells. Additionally,downregulating PSMB10 also impeded MHC-I protein degradation-induced escape of CTL killing. PSMB10 is a key candidate molecular target for eradicating drug-resistant LSCs via senescence and immune regulation. The online version contains supplementary material available at 10.1186/s13046-025-03420-9. View Publication

Interleukin-6 (IL-6) is a critical factor in the regulation of stromal function and hematopoiesis. In vivo bromodeoxyuridine incorporation analysis indicates that the percentage of Lin(-)Sca-1(+) hematopoietic progenitors undergoing DNA synthesis is diminished in IL-6-deficient (IL-6(-/-)) bone marrow (BM) compared with wild-type BM. Reduced proliferation of IL-6(-/-) BM progenitors is also observed in IL-6(-/-) long-term BM cultures,which show defective hematopoietic support as measured by production of total cells,granulocyte macrophage-colony-forming units (CFU-GMs),and erythroid burst-forming units (BFU-Es). Seeding experiments of wild-type and IL-6(-/-) BM cells on irradiated wild-type or IL-6-deficient stroma indicate that the hematopoietic defect can be attributed to the stromal and not to the hematopoietic component. In IL-6(-/-) BM,stromal mesenchymal precursors,fibroblast CFUs (CFU-Fs),and stroma-initiating cells (SICs) are reduced to almost 50% of the wild-type BM value. Moreover,IL-6(-/-) stromata show increased CD34 and CD49e expression and reduced expression of the membrane antigens vascular cell adhesion molecule-1 (VCAM-1),Sca-1,CD49f,and Thy1. These data strongly suggest that IL-6 is an in vivo growth factor for mesenchymal precursors,which are in part implicated in the reduced longevity of the long-term repopulating stem cell compartment of IL-6(-/-) mice. View Publication

We investigated the involvement of the urokinase-type plasminogen-activator receptor (uPAR) in granulocyte-colony-stimulating factor (G-CSF)-induced mobilization of CD34+ hematopoietic stem cells (HSCs) from 16 healthy donors. Analysis of peripheral blood mononuclear cells (PBMNCs) showed an increased uPAR expression after G-CSF treatment in CD33+ myeloid and CD14+ monocytic cells,whereas mobilized CD34+ HSCs remained uPAR negative. G-CSF treatment also induced an increase in serum levels of soluble uPAR (suPAR). Cleaved forms of suPAR (c-suPAR) were released in vitro by PBMNCs and were also detected in the serum of G-CSF-treated donors. c-suPAR was able to chemoattract CD34+ KG1 leukemia cells and CD34+ HSCs,as documented by their in vitro migratory response to a chemotactic suPAR-derived peptide (uPAR84-95). uPAR84-95 induced CD34+ KG1 and CD34+ HSC migration by activating the high-affinity fMet-Leu-Phe (fMLP) receptor (FPR). In addition,uPAR84-95 inhibited CD34+ KG1 and CD34+ HSC in vitro migration toward the stromal-derived factor 1 (SDF1),thus suggesting the heterologous desensitization of its receptor,CXCR4. Finally,uPAR84-95 treatment significantly increased the output of clonogenic progenitors from long-term cultures of CD34+ HSCs. Our findings demonstrate that G-CSF-induced upregulation of uPAR on circulating CD33+ and CD14+ cells is associated with increased uPAR shedding,which leads to the appearance of serum c-suPAR. c-suPAR could contribute to the mobilization of HSCs by promoting their FPR-mediated migration and by inducing CXCR4 desensitization. View Publication

The termination of activation signals is a critical step in the control of the immune response; perturbation of inhibitory feedback pathways results in profound immune defects culminating in autoimmunity and overwhelming inflammation. FcgammaRIIB receptor is a well described inhibitory receptor. The ligation of B-cell receptor (BCR) and FcgammaRIIB leads to the inhibition of B-cell activation. Numerous studies have demonstrated that the SH2-domain-containing inositol 5-phosphatase SHIP (referred hereto as SHIP-1) is essential in this process. The cDNA encoding a second SH2-domain-containing inositol 5-phosphatase,SHIP-2,has been cloned [Pesesse,Deleu,De Smedt,Drayer and Erneux (1997) Biochem. Biophys. Res. Commun. 239,697-700]. Here we report the distribution of SHIP-2 in mouse tissues: a Western blot analysis of mouse tissues reveals that SHIP-2 is expressed in both haemopoietic and non-haemopoietic cells. In addition to T-cell and B-cell lines,spleen,thymus and lung are shown to coexpress SHIP-1 and SHIP-2. Moreover,SHIP-2 is detected in fibroblasts,heart and different brain areas. SHIP-2 shows a maximal tyrosine phosphorylation and association to Shc after ligation of BCR to FcgammaRIIB but not after stimulation of BCR alone. Our results therefore suggest a possible role for SHIP-2 in the negative regulation of immunocompetent cells. View Publication

Hematopoietic stem cells (HSCs) reside in the bone marrow within niches that provide microenvironmental signals in the form of biophysical cues,bound and diffusible biomolecules,and heterotypic cell-cell interactions that influence HSC fate decisions. This study seeks to inform the development of a synthetic culture platform that promotes ex vivo HSC expansion without exhaustion. A library of methacrylamide-functionalized gelatin (GelMA) hydrogels is used to explore remodeling and crosstalk from mesenchymal stromal cells (MSCs) on the expansion and quiescence of murine HSCs. The use of a degradable GelMA hydrogel enables MSC-mediated remodeling,yielding dynamic shifts in the matrix environment over time. An initially low-diffusivity hydrogel for co-culture of hematopoietic stem and progenitor cells to MSCs facilitates maintenance of an early progenitor cell population over 7 days. Excitingly,this platform promotes retention of a quiescent HSC population compared to HSC monocultures. These studies reveal MSC-density-dependent upregulation of MMP-9 and changes in hydrogel mechanical properties ($\Delta$E = 2.61 ± 0.72) suggesting MSC-mediated matrix remodeling may contribute to a dynamic culture environment. Herein,a 3D hydrogel is reported for ex vivo HSC culture,in which HSC expansion and quiescence is sensitive to hydrogel properties,MSC co-culture,and MSC-mediated hydrogel remodeling. View Publication

Transforming growth factor-beta1 (TGF-beta1) is a pleiotropic cytokine with major in vitro effects on hematopoietic stem cells (HSCs) and lymphocyte development. Little is known about hematopoiesis from mice with constitutive TGF-beta1 inactivation largely because of important embryonic lethality and development of a lethal inflammatory disorder in TGF-beta1(-/-) pups,making these studies difficult. Here,we show that no sign of the inflammatory disorder was detectable in 8- to 10-day-old TGF-beta1(-/-) neonates as judged by both the number of T-activated and T-regulator cells in secondary lymphoid organs and the level of inflammatory cytokines in sera. After T-cell depletion,the inflammatory disease was not transplantable in recipient mice. Bone marrow cells from 8- to 10-day-old TGF-beta1(-/-) neonates showed strikingly impaired short- and long-term reconstitutive activity associated with a parallel decreased in vivo homing capacity of lineage negative (Lin(-)) cells. In addition an in vitro-reduced survival of immature progenitors (Lin(-) Kit(+) Sca(+)) was observed. Similar defects were found in liver cells from TGF-beta1(-/-) embryos on day 14 after vaginal plug. These data indicate that TGF-beta1 is a critical regulator for in vivo homeostasis of the HSCs,especially for their homing potential. View Publication

AbstractBackgroundChimeric antigen receptor (CAR) therapies have demonstrated potent efficacy in treating B-cell malignancies,but have yet to meaningfully translate to solid tumors. Nonetheless,they are of particular interest for the treatment of glioblastoma,which is an aggressive form of brain cancer with few effective therapeutic options,due to their ability to cross the highly selective blood-brain barrier.MethodsHere,we use our pooled screening platform,CARPOOL,to expedite the discovery of CARs with antitumor functions necessary for solid tumor efficacy. We performed selections in primary human T cells expressing a library of 1.3×106 third generation CARs targeting IL-13Rα2,a cancer testis antigen commonly expressed in glioblastoma. Selections were performed for cytotoxicity,proliferation,memory formation,and persistence on repeated antigen challenge.ResultsEach enriched CAR robustly produced the phenotype for which it was selected,and one enriched CAR triggered potent cytotoxicity and long-term proliferation on in vitro tumor rechallenge. It also showed significantly improved persistence and comparable tumor control in a microphysiological human in vitro model and a xenograft model of human glioblastoma,but also demonstrated increased off-target recognition of IL-13Rα1.ConclusionTaken together,this work demonstrates the utility of extending CARPOOL to diseases beyond hematological malignancies and represents the largest exploration of signaling combinations in human primary cells to date. View Publication