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

Microfluidic systems create significant opportunities to establish highly controlled microenvironmental conditions for screening pluripotent stem cell fate. However,since cell fate is crucially dependent on this microenvironment,it remains unclear as to whether continual perfusion of culture medium supports pluripotent stem cell maintenance in feeder-free,chemically defined conditions,and further,whether optimum perfusion conditions exist for subsequent use of human embryonic stem cell (hESCs) in other microfludic systems. To investigate this,we designed microbioreactors based on resistive flow to screen hESCs under a linear range of flowrates. We report that at low rates (conditions where glucose transport is convection-limited with Péclet number textless1),cells are affected by apparent nutrient depletion and waste accumulation,evidenced by reduced cell expansion and altered morphology. At higher rates,cells are spontaneously washed out,and display morphological changes which may be indicative of early-stage differentiation. However,between these thresholds exists a narrow range of flowrates in which hESCs expand comparably to the equivalent static culture system,with regular morphology and maintenance of the pluripotency marker TG30 in textgreater95% of cells over 7 days. For MEL1 hESCs the optimum flowrate also coincided with the time-averaged medium exchange rate in static cultures,which may therefore provide a good first estimate of appropriate perfusion rates. Overall,we demonstrate hESCs can be maintained in microbioreactors under continual flow for up to 7 days,a critical outcome for the future development of microbioreactor-based screening systems and assays for hESC culture. View Publication

BackgroundSeveral approaches are being explored for engineering off-the-shelf chimeric antigen receptor (CAR) T cells. In this study,we engineered chimeric Fcγ receptor (FcγR) T cells and tested their potential as a versatile platform for universal T cell therapy.MethodsChimeric FcγR (CFR) constructs were generated using three distinct forms of FcγR,namely CD16A,CD32A,and CD64. The functionality of CFR T cells was evaluated through degranulation assays,specific target lysis experiments,in vitro cytokine production analysis,and assessment of tumor xenograft destruction specificity in mouse models using different monoclonal antibodies (MoAbs).ResultsThree types of CFR T cells were engineered,16s3,32-8a,64-8a CFR T cells. In the presence of rituximab (RTX),cytotoxicity of all three types of CFR T cells against CD20+ Raji-wt,K562-CD20+,and primary tumor cells was significantly higher than that of the mock T cells (P < 0.001). When herceptin was used,all three types of CFR T cells exhibited significant cytotoxicity against HER2+ cell lines of SK-BR-3,SK-OV-3,and HCC1954 (P < 0.001). The cytotoxicity of 64-8a CFR T cells was significantly inhibited by free human IgG at a physiological dose (P < 0.001),which was not observed in 16s3,32-8a CFR T cells. Compared to 32-8a CFR T cells,16s3 CFR T cells exhibited more prolonged cytotoxicity than 32-8a CFR T cells (P < 0.01). In in vivo assays using xenograft models,16s3 CFR T cells significantly prolonged the survival of mice xenografted with Raji-wt cells in the presence of RTX (P < 0.001),and effectively reduced tumor burden in mice xenografted with SK-OV-3 cells in the presence of herceptin (P < 0.05). No significant non-specific cytotoxicity of CFR T cells was found in vivo.ConclusionThe anti-tumor effects of the CFR T cells in vitro and in xenograft mouse models are mediated by specific MoAbs such as RTX and herceptin. The CFR T cells therefore have the features of universal T cells with specificity directed by MoAbs. 16s3 CFR T cells are chosen for clinical trials.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40164-025-00595-x. View Publication

Lupus glomerulonephritis (GN) is an autoimmune disease characterized by immune complex-deposition,complement activation and glomerular inflammation. In lupus-prone NZM2328 mice,the occurrence of lupus GN was accompanied by a decrease in Treg cells and an increase in proinflammatory cytokine-producing T cells. Because IL-33 in addition to IL-2 has been shown to be important for Treg cell proliferation and ST2 (IL-33 receptor) positive Treg cells are more potent in suppressor activity,a hybrid cytokine with active domains of IL-2 and IL-33 was generated to target the ST2+ Treg cells as a therapeutic agent to treat lupus GN. Three mouse models were used: spontaneous and Ad-IFNalpha- accelerated lupus GN in NZM2328 and the lymphoproliferative autoimmune GN in MRL/lpr mice. Daily injections of IL233 for 5 days prevented Ad-IFNalpha-induced lupus GN and induced remission of spontaneous lupus GN. The remission was permanent in that no relapses were detected. The remission was accompanied by persistent elevation of Treg cells in the renal lymph nodes. IL233 is more potent than IL-2 and IL-33 either singly or in combination in the treatment of lupus GN. The results of this study support the thesis that IL233 should be considered as a novel agent for treating lupus GN. View Publication

Haematopoietic stem cell (HSC) gene therapy has demonstrated potential to treat many diseases. However,current state of the art requires sophisticated ex vivo gene transfer in a dedicated Good Manufacturing Practices facility,limiting availability. An automated process would improve the availability and standardized manufacture of HSC gene therapy. Here,we develop a novel program for semi-automated cell isolation and culture equipment to permit complete benchtop generation of gene-modified CD34+ blood cell products for transplantation. These cell products meet current manufacturing quality standards for both mobilized leukapheresis and bone marrow,and reconstitute human haematopoiesis in immunocompromised mice. Importantly,nonhuman primate autologous gene-modified CD34+ cell products are capable of stable,polyclonal multilineage reconstitution with follow-up of more than 1 year. These data demonstrate proof of concept for point-of-care delivery of HSC gene therapy. Given the many target diseases for gene therapy,there is enormous potential for this approach to treat patients on a global scale. View Publication

Cell surface biomarkers have been applied to discriminate pluripotent human embryonic stem cells and induced pluripotent stem cells from differentiated cells. Here,we demonstrate that a recombinant lectin probe,rBC2LCN,a new tool for fluorescence-based imaging and flow cytometry analysis of pluripotent stem cells,is an alternative to conventional pluripotent maker antibodies. Live or fixed colonies of both human embryonic stem cells and induced pluripotent stem cells were visualized in culture medium containing fluorescent dye-labeled rBC2LCN. Fluorescent dye-labeled rBC2LCN was also successfully used to separate live pluripotent stem cells from a mixed cell population by flow cytometry. textcopyright 2013 Elsevier Inc. View Publication

Embryonic stem (ES) cells are characterized by pluripotency,defined as the developmental potential to generate cell lineages derived from all three primary germ layers. In the past decade,great progress has been made on the cell culture conditions,transcription factor programs and intracellular signaling pathways that control both murine and human ES cell fates. ES cells of mouse vs. human origin have distinct culture conditions,responding to some tyrosine kinase signaling pathways in opposite ways. Previous work has implicated the Src family of non-receptor protein-tyrosine kinases in mouse ES cell self-renewal and differentiation. Seven members of the Src kinase family are expressed in mouse ES cells,and individual family members appear to play distinct roles in regulating their developmental fate. Both Hck and c-Yes are important in self-renewal,while c-Src activity alone is sufficient to induce differentiation. While these findings implicate Src-family kinase signaling in mouse ES cell renewal and differentiation,the role of this kinase family in human ES cells is largely unknown. Here,we explored Src-family kinase expression patterns and signaling in human ES cells during self-renewal and differentiation. Of the eleven Src-related kinases in the human genome,Fyn,c-Yes,c-Src,Lyn,Lck and Hck were expressed in H1,H7 and H9 hES cells,while Fgr,Blk,Srm,Brk,and Frk transcripts were not detected. Of these,c-Yes,Lyn,and Hck transcript levels remained constant in self-renewing human ES cells vs. differentiated EBs,while c-Src and Fyn showed a modest increase in expression as a function of differentiation. In contrast,Lck expression levels dropped dramatically as a function of EB differentiation. To assess the role of overall Src-family kinase activity in human ES cell differentiation,cultures were treated with inhibitors specific for the Src kinase family. Remarkably,human ES cells maintained in the presence of the potent Src-family kinase inhibitor A-419259 retained the morphology of domed,pluripotent colonies and continued to express the self-renewal marker TRA-1-60 despite culture under differentiation conditions. Taken together,these observations support a role for Src-family kinase signaling in the regulation of human ES cell fate,and suggest that the activities of individual Src-family members are required for the initiation of the differentiation program. View Publication

A major challenge in developing gene-based therapies for airway diseases such as cystic fibrosis (CF) is sustaining therapeutic levels of transgene expression over time. This is largely due to airway epithelial cell turnover and the host immunogenicity to gene delivery vectors. Modern gene editing tools and delivery vehicles hold great potential for overcoming this challenge. There is currently not much known about how to deliver genes into airway stem cells,of which basal cells are the major type in human airways. In this study,helper-dependent adenoviral (HD-Ad) vectors were delivered to mouse and pig airways via intranasal delivery,and direct bronchoscopic instillation,respectively. Vector transduction was assessed by immunostaining of lung tissue sections,which revealed that airway basal cells of mice and pigs can be targeted in vivo. In addition,efficient transduction of primary human airway basal cells was verified with an HD-Ad vector expressing green fluorescent protein. Furthermore,we successfully delivered the human CFTR gene to airway basal cells from CF patients,and demonstrated restoration of CFTR channel activity following cell differentiation in air-liquid interface culture. Our results provide a strong rationale for utilizing HD-Ad vectors to target airway basal cells for permanent gene correction of genetic airway diseases. View Publication

Despite the success of chimeric antigen receptor T (CART) cell therapy in hematological malignancies,durable remissions remain low. Here,we report CART senescence as a potential resistance mechanism in 41BB-costimulated CART cell therapy. To mimic cancer relapse,we utilized an in vitro model with repeated CART cell activation cycles followed by rest periods. Using CD19-targeted CART cells with costimulation via 4-1BB-CD3ζ (BBζ) or CD28-CD3ζ (28ζ),we showed that CART cells undergo functional,phenotypical,and transcriptomic changes of senescence,which is more prominent in BBζ. We then utilized two additional independent strategies to induce senescence through MYC activation and irradiation. Induction of senescence impaired BBζ activity but improved 28ζ activity in preclinical studies. These findings were supported by analyses of independent patient data sets; senescence signatures in CART cell products were associated with non-response to BBζ but with improved clinical outcomes in 28ζ treatment. In summary,our study identifies senescence as a potential mechanism of failure predominantly in 41BB-costimulated CART cells.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12943-025-02371-1. SignificanceWe identified senescence as a cause of failure in CART cell therapy,predominantly in 4-1BB-costimulated CART cells.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12943-025-02371-1. View Publication

Genetic modification of hematopoietic stem cells often results in the expression of foreign proteins in pluripotent progenitor cells and their progeny. However,the potential for products of foreign genes introduced into hematopoietic stem cells to induce host immune responses is not well understood. Gene marking and induction of immune responses to enhanced green fluorescent protein (eGFP) were examined in rhesus macaques that underwent nonmyeloablative irradiation followed by infusions of CD34(+) bone marrow cells transduced with a retroviral vector expressing eGFP. CD34(+) cells were obtained from untreated animals or from animals treated with recombinant human granulocyte colony-stimulating factor (G-CSF) alone or G-CSF and recombinant human stem cell factor. Levels of eGFP-expressing cells detected by flow cytometry peaked at 0.1% to 0.5% of all leukocytes 1 to 4 weeks after transplantation. Proviral DNA was detected in 0% to 17% of bone marrow--derived colony-forming units at periods of 5 to 18 weeks after transplantation. However,5 of 6 animals studied demonstrated a vigorous eGFP-specific cytotoxic T lymphocyte (CTL) response that was associated with a loss of genetically modified cells in peripheral blood,as demonstrated by both flow cytometry and polymerase chain reaction. The eGFP-specific CTL responses were MHC-restricted,mediated by CD8(+) lymphocytes,and directed against multiple epitopes. eGFP-specific CTLs were able to efficiently lyse autologous CD34(+) cells expressing eGFP. Antibody responses to eGFP were detected in 3 of 6 animals. These data document the potential for foreign proteins expressed in CD34(+) hematopoietic cells and their progeny to induce antibody and CTL responses in the setting of a clinically applicable transplantation protocol. (Blood. 2001;97:1951-1959) View Publication

Umbilical cord blood (UCB) transplants in adults have slower hematopoietic recovery compared to bone marrow (BM) or peripheral blood (PB) stem cells mainly due to low number of total nucleated cells and hematopoietic stem and progenitor cells (HSPC). As such in this study,we aimed to perform ex vivo expansion of UCB HSPC from non-enriched mononucleated cells (MNC) using novel azole-based small molecules. Freshly-thawed UCB-MNC were cultured in expansion medium supplemented with small molecules and basal cytokine cocktail. The effects of the expansion protocol were measured based on in vitro and in vivo assays. The proprietary library of {\textgreater}50 small molecules were developed using structure-activity-relationship studies of SB203580,a known p38-MAPK inhibitor. A particular analog,C7,resulted in 1,554.1 ± 27.8-fold increase of absolute viable CD45+ CD34+ CD38- CD45RA- progenitors which was at least 3.7-fold higher than control cultures (p {\textless} .001). In depth phenotypic analysis revealed {\textgreater}600-fold expansion of CD34+ /CD90+ /CD49f+ rare HSPCs coupled with significant (p {\textless} .01) increase of functional colonies from C7 treated cells. Transplantation of C7 expanded UCB grafts to immunodeficient mice resulted in significantly (p {\textless} .001) higher engraftment of human CD45+ and CD45+ CD34+ cells in the PB and BM by day 21 compared to non-expanded and cytokine expanded grafts. The C7 expanded grafts maintained long-term human multilineage chimerism in the BM of primary recipients with sustained human CD45 cell engraftment in secondary recipients. In conclusion,a small molecule,C7,could allow for clinical development of expanded UCB grafts without pre-culture stem cell enrichment that maintains in vitro and in vivo functionality. Stem Cells Translational Medicine 2018;7:376-393. View Publication

Glioblastoma is the most common form of primary malignant brain tumour. These tumours are highly proliferative and infiltrative resulting in a median patient survival of only 14 months from diagnosis. The current treatment regimens are ineffective against the small population of cancer stem cells residing in the tumourigenic niche; however,a new therapeutic approach could involve the removal of these cells from the microenvironment that maintains the cancer stem cell phenotype. We have isolated multipotent sphere-forming cells from human high grade glioma (glioma sphere-forming cells (GSCs)) to investigate the adhesive and migratory properties of these cells in vitro. We have focused on the role of two closely related metalloproteinases ADAM10 and ADAM17 due to their high expression in glioblastoma and GSCs and their ability to activate cytokines and growth factors. Here,we report that ADAM10 and ADAM17 inhibition selectively increases GSC,but not neural stem cell,migration and that the migrated GSCs exhibit a differentiated phenotype. We also observed a correlation between nestin,a stem/progenitor marker,and fibronectin,an extracellular matrix protein,expression in high grade glioma tissues. GSCs adherence on fibronectin is mediated by α5β1 integrin,where fibronectin further promotes GSC migration and is an effective candidate for in vivo cancer stem cell migration out of the tumourigenic niche. Our results suggest that therapies against ADAM10 and ADAM17 may promote cancer stem cell migration away from the tumourigenic niche resulting in a differentiated phenotype that is more susceptible to treatment. View Publication

NOTCH signaling is critical for specifying the intestinal epithelial cell lineage and for initiating colorectal adenomas and colorectal cancers (CRC). Based on evidence that NOTCH is important for the maintenance and self-renewal of cancer-initiating cells in other malignancies,we studied the role of NOTCH signaling in colon cancer-initiating cells (CCIC). Tumors formed by CCICs maintain many properties of the primary CRCs from which they were derived,such as glandular organization,cell polarity,gap junctions,and expression of characteristic CRC molecular markers. Furthermore,CCICs have the property of self-renewal. In this study,we show that NOTCH signaling is 10- to 30-fold higher in CCIC compared with widely used colon cancer cell lines. Using small-molecule inhibition and short hairpin RNA knockdown,we show that NOTCH prevents CCIC apoptosis through repression of cell cycle kinase inhibitor p27 and transcription factor ATOH1. NOTCH is also critical to intrinsic maintenance of CCIC self-renewal and the repression of secretory cell lineage differentiation genes such as MUC2. Our findings describe a novel human cell system to study NOTCH signaling in CRC tumor initiation and suggest that inhibition of NOTCH signaling may improve CRC chemoprevention and chemotherapy. View Publication