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

Although aldehyde dehydrogenase (ALDH) activity has become a surrogate of hematopoietic stem and progenitor cells (HSPCs),its function during hematopoiesis was unclear. Here,we examined its role in zebrafish hematopoiesis based on pharmacological inhibition and morpholino (MO) knockdown. Zebrafish embryos were treated with diethylaminobenzaldehyde (DEAB,1 μmol/l) between 0- and 48 hour-post-fertilization (hpf). MOs targeting aldhs were injected between 1 and 4-cell stage. The effects on hematopoiesis were evaluated at different stages. DEAB treatment between 0 and 18 hpf increased gene expression associated with HSPC (scl,lmo2),erythropoiesis (gata1,α- and β-eHb) and myelopoiesis (spi1) as well as gfp(+) cells in dissociated Tg(gata1:gfp) embryos. The effects were ameliorated by all-trans retinoic acid (1 nmol/l). Definitive hematopoiesis and the erythromyeloid precursors were unaffected. In all,14 out of 15 zebrafish aldhs were detectable by reverse transcription PCR in 18 hpf embryos,of which only aldh1a2 and aldh16a1 were expressed in sites pertinent to hematopoiesis. Molecular targeting by MOs was demonstrated for 15 aldhs,but none of them,even in combined aldh1a2 and aldh1a3 knockdown,recapitulated the hematopoietic expansion in DEAB-treated embryos. In conclusion,DEAB expands HSPC population during primitive hematopoiesis through inhibition of aldh and retinoic acid synthesis. The specific aldh isoform(s) remains to be determined. View Publication

p18 INK4 C (CDKN2C,encoded by p18 INK4c or Cdkn2c ) is an early G1-phase cyclin-dependent kinase inhibitor protein. Previous studies demonstrated enhanced self-renewal capacity of hematopoietic stem cells (HSCs) in p18 −/− mice compared to wild-type (WT) mice. Given the critical role of bone marrow niche cells-particularly mesenchymal stromal cells (MSCs)-in hematopoiesis,this study investigated the functional alterations of p18 −/− MSCs and their impact on hematopoietic support. Bone marrow derived MSCs were isolated from p18 −/− and WT mice. Their proliferation and differentiation capacities were assessed,followed by evaluation of hematopoietic support using cobblestone area-forming cell assay and long-term culture-initiating cell assay. RNA sequencing was performed to analyze the transcriptional profile of p18 −/− MSCs,with a focus on differentially expressed genes (DEGs). Key pathways associated with hematopoietic support were identified using Ingenuity Pathway Analysis. A candidate protein was quantified by ELISA,and its functional role in hematopoietic support was validated via a modified coculture system. p18 −/− MSCs displayed an increased proliferation rate,preferential differentiation toward osteogenesis over adipogenesis,and enhanced hematopoietic support. RNA sequencing analysis identified 137 DEGs,with secreted phosphoprotein 1 ( Spp1,encoding osteopontin,Opn) being significantly upregulated in p18 −/− MSCs. Elevated Opn levels were confirmed in both bone marrow and MSC-conditioned media from p18 −/− mice. Functional validation further demonstrated that Opn enhanced the hematopoietic supportive capacity of MSCs in vitro. p18 deficiency promotes osteogenic differentiation and enhances the hematopoietic supportive function of MSCs,likely mediated by Opn upregulation. These findings suggest a potential therapeutic strategy for improving bone regeneration and HSC expansion. The online version contains supplementary material available at 10.1186/s13287-025-04402-6. View Publication

Haematopoietic stem cells (HSCs) have the ability to renew themselves and to give rise to all lineages of the blood; however,the signals that regulate HSC self-renewal remain unclear. Here we show that the Wnt signalling pathway has an important role in this process. Overexpression of activated beta-catenin expands the pool of HSCs in long-term cultures by both phenotype and function. Furthermore,HSCs in their normal microenvironment activate a LEF-1/TCF reporter,which indicates that HCSs respond to Wnt signalling in vivo. To demonstrate the physiological significance of this pathway for HSC proliferation we show that the ectopic expression of axin or a frizzled ligand-binding domain,inhibitors of the Wnt signalling pathway,leads to inhibition of HSC growth in vitro and reduced reconstitution in vivo. Furthermore,activation of Wnt signalling in HSCs induces increased expression of HoxB4 and Notch1,genes previously implicated in self-renewal of HSCs. We conclude that the Wnt signalling pathway is critical for normal HSC homeostasis in vitro and in vivo,and provide insight into a potential molecular hierarchy of regulation of HSC development. View Publication

Differentiation of embryonic stem (ES) cells typically requires cell-cell aggregation in the form of embryoid bodies (EBs). This process is not very well controlled and final cell numbers can be limited by EB agglomeration and the inability to drive differentiation towards a desired cell type. This study compares three-dimensional (3D) fibrin culture to conventional two-dimensional (2D) suspension culture and to culture in a semisolid methylcellulose medium solution. Two types of fibrin culture were evaluated,including a PEGylated fibrin gel. PEGylation with a difunctional PEG derivative retarded fibrinogen migration during through sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) as a result of crosslinking,similarly,degradation was slowed in the PEGylated gel. ES cell proliferation was higher in both the fibrin and PEGylated fibrin gels versus 2D and methylcellulose controls. FACS analysis and real-time-PCR revealed differences in patterns of differentiation for the various culture systems. Culture in PEGylated fibrin or methylcellulose culture demonstrated features characteristic of less extensive differentiation relative to fibrin and 2D culture as evidenced by the transcription factor Oct-4. Fibrin gels showed gene and protein expression similar to that in 2D culture. Both fibrin and 2D cultures demonstrated statistically greater cell numbers positive for the vascular mesoderm marker,VE-cadherin. View Publication

Administration of bone marrow-derived mesenchymal stem cells (MSCs) is an innovative approach for the treatment of a range of diseases that are not curable by current therapies including heart failure. A number of clinical trials have been completed and many others are ongoing; more than 2,000 patients worldwide have been administered with culture-expanded allogeneic or autologous MSCs for the treatment of various diseases,showing feasibility and safety (and some efficacy) of this approach. However,protocols for isolation and expansion of donor MSCs vary widely between these trials,which could affect the efficacy of the therapy. It is therefore important to develop international standards of MSC production,which should be evidence-based,regulatory authority-compliant,of good medical practice grade,cost-effective,and clinically practical,so that this innovative approach becomes an established widely adopted treatment. This review article summarizes protocols to isolate and expand bone marrow-derived MSCs in 47 recent clinical trials of MSC-based therapy,which were published after 2007 onwards and provided sufficient methodological information. Identified issues and possible solutions associated with the MSC production methods,including materials and protocols for isolation and expansion,are discussed with reference to relevant experimental evidence with aim of future clinical success of MSC-based therapy. View Publication

Immunosuppressants are powerful drugs,capable of triggering severe adverse effects. Hence,there is tremendous interest in replacing them with less-toxic agents. Adoptive therapy with CD25(+)CD4(+) T regulatory cells (Tregs) holds promise as an alternative to immunosuppressants. Tregs have been described as the most potent immunosuppressive cells in the human body. In a number of experimental models,they have been found to quench autoimmune diseases,maintain allogeneic transplants,and prevent allergic diseases. A major stumbling block in their clinical application is related to Treg phenotype and the very limited number of these cells in the periphery,not exceeding 1-5% of total CD4(+) T cells. Recent progress in multicolor flow cytometry and cell sorting as well as cellular immunology has found ways of overcoming these obstacles,and has opened the doors to the clinical application of Tregs. In the review,we describe Treg sorting and expansion techniques that have been developed in recent years. In the experience of our laboratory,as well as some published reports,Treg adoptive therapy is a promising tool in immunosuppressive therapy,and should be considered for clinical trials. View Publication

BACKGROUND Patients with gene expression profiling-defined high-risk myeloma in relapse have poor outcomes with current therapies. We tested whether natural killer cells expanded by co-culture with K562 cells transfected with 41BBL and membrane-bound interleukin-15 could kill myeloma cells with a high-risk gene expression profile in vitro and in a unique model which recapitulates human myeloma. DESIGN AND METHODS OPM2 and high-risk primary myeloma tumors were grown in human fetal bone implanted into non-obese diabetic severe combined immunodeficiency mice with a deficient interleukin-2 receptor gamma chain. These mice are devoid of endogenous natural killer and T-cell activity and were used to determine whether adoptively transferred expanded natural killer cells could inhibit myeloma growth and myeloma-associated bone destruction. RESULTS Natural killer cells from healthy donors and myeloma patients expanded a median of 804- and 351-fold,respectively,without significant T-cell expansion. Expanded natural killer cells killed both allogeneic and autologous primary myeloma cells avidly via a perforin-mediated mechanism in which the activating receptor NKG2D,natural cytotoxicity receptors,and DNAX-accessory molecule-1 played a central role. Adoptive transfer of expanded natural killer cells inhibited the growth of established OPM2 and high-risk primary myeloma tumors grown in the murine model. The transferred,expanded natural killer cells proliferated in vivo in an interleukin-2 dose-dependent fashion,persisted up to 4 weeks,were readily detectable in the human bone,inhibited myeloma growth and protected bone from myeloma-induced osteolysis. CONCLUSIONS These studies provide the rationale for testing expanded natural killer cells in humans. View Publication

Circulating Tumor Cells (CTCs) represent an easy,repeatable and representative access to information regarding solid tumors. However,their detection remains difficult because of their paucity,their short half-life,and the lack of reliable surface biomarkers. Flow cytometry (FC) is a fast,sensitive and affordable technique,ideal for rare cells detection. Adapted to CTCs detection (i.e. extremely rare cells),most FC-based techniques require a time-consuming pre-enrichment step,followed by a 2-hours staining procedure,impeding on the efficiency of CTCs detection. We overcame these caveats and reduced the procedure to less than one hour,with minimal manipulation. First,cells were simultaneously fixed,permeabilized,then stained. Second,using low-speed FC acquisition conditions and two discriminators (cell size and pan-cytokeratin expression),we suppressed the pre-enrichment step. Applied to blood from donors with or without known malignant diseases,this protocol ensures a high recovery of the cells of interest independently of their epithelial-mesenchymal plasticity and can predict which samples are derived from cancer donors. This proof-of-concept study lays the bases of a sensitive tool to detect CTCs from a small amount of blood upstream of in-depth analyses. View Publication

The advent of clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-based genome editing has marked a significant advancement in genetic engineering technology. However,the editing of induced pluripotent stem cells (iPSCs) with CRISPR presents notable challenges in ensuring cell survival and achieving high editing efficiency. These challenges become even more complex when considering the specific target site. P53 activation as a result of traditional CRISPR editing can lead to apoptosis,potentially worsening cell health or even resulting in cell death. Mitigating this apoptotic response can enhance cell survival post-CRISPR editing,which will ultimately increase editing efficiency. In our study,we observed that combining p53 inhibition with pro-survival small molecules yields a homologous recombination rate of over 90% when using CRISPR in human iPSCs. This protocol significantly streamlines the editing process and reduces the time and resources necessary for creating isogenic lines. View Publication

CD8+ effector T (TE) cell proliferation and cytokine production depends on enhanced glucose metabolism. However,circulating T cells continuously adapt to glucose fluctuations caused by diet and inter-organ metabolite exchange. Here we show that transient glucose restriction (TGR) in activated CD8+ TE cells metabolically primes effector functions and enhances tumour clearance in mice. Tumour-specific TGR CD8+ TE cells co-cultured with tumour spheroids in replete conditions display enhanced effector molecule expression,and adoptive transfer of these cells in a murine lymphoma model leads to greater numbers of immunologically functional circulating donor cells and complete tumour clearance. Mechanistically,TE cells treated with TGR undergo metabolic remodelling that,after glucose re-exposure,supports enhanced glucose uptake,increased carbon allocation to the pentose phosphate pathway (PPP) and a cellular redox shift towards a more reduced state-all indicators of a more anabolic programme to support their enhanced functionality. Thus,metabolic conditioning could be used to promote efficiency of T-cell products for adoptive cellular therapy. View Publication

Transplantation of photoreceptor precursor cells (PPCs) differentiated from human embryonic stem cells (hESCs) is a promising approach to treat common blinding diseases such as age-related macular degeneration and retinitis pigmentosa. However,existing PPC generation methods are inefficient. To enhance differentiation protocols for rapid and high-yield production of PPCs,we focused on optimizing the handling of the cells by including feeder-independent growth of hESCs,using size-controlled embryoid bodies (EBs),and addition of triiodothyronine (T3) and taurine to the differentiation medium,with subsequent removal of undifferentiated cells via negative cell-selection. Our novel protocol produces higher yields of PPCs than previously reported while reducing the time required for differentiation,which will help understand retinal diseases and facilitate large-scale preclinical trials. View Publication

BACKGROUND Many groups have generated insulin-secreting cells from hESCs/iPSCs in multiple differentiation stages by mimicking the developmental processes. However,these cells do not always secrete glucose responsive insulin,one of the most important characteristics of pancreatic $$ cells. We focused on the importance of endodermal differentiation from human iPSCs in order to obtain functional pancreatic $$ cells. METHODS We established a 6-stage protocol for the differentiation process from hiPSCs to pancreatic $$ cells using defined culture media without feeders or serum. We examined the effect of CHIR99021,the selective inhibitor of GSK-3$$,in the presence of Activin,FGF2,and BMP4 during definitive endodermal induction by immunostaining for SOX17 and FOXA2. We also compared the insulin secretion at the last stage between monolayer culture and spheroid culture conditions. Cultured cells were transplanted under the kidney capsules of STZ-induced diabetic NOD-SCID mice,and blood glucose levels were measured. Immunohistochemical analysis was performed 4 weeks and 12 weeks after transplantation. RESULTS Addition of CHIR99021 in the presence of Activin,FGF2,and BMP4 for 2 days improved the viability of the endodermal cells,keeping the high positive rate of SOX17. Spheroid formation after the endocrine progenitor stage showed more efficient insulin secretion than monolayer culture did. After cell transplantation,diabetic mice showed lowered blood glucose levels,and we detected islet-like structures in vivo. CONCLUSION We generated functional pancreatic $$ cells from human iPS cells. Induction of definitive endoderm and spheroid formation might be key steps for producing them. View Publication