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

Preclinical in vitro models provide an essential tool to study cancer cell biology as well as aid in translational research,including drug target identification and drug discovery efforts. For any model to be clinically relevant,it needs to recapitulate the biology and cell heterogeneity of the primary tumor. We recently developed and described a conditional reprogramming (CR) cell technology that addresses many of these needs and avoids the deficiencies of most current cancer cell lines,which are usually clonal in origin. Here,we used the CR cell method to generate a collection of patient-derived cell cultures from non-small cell lung cancers (NSCLC). Whole exome sequencing and copy number variations are used for the first time to address the capability of CR cells to keep their tumor-derived heterogeneity. Our results indicated that these primary cultures largely maintained the molecular characteristics of the original tumors. Using a mutant-allele tumor heterogeneity (MATH) score,we showed that CR cells are able to keep and maintain most of the intra-tumoral heterogeneity,suggesting oligoclonality of these cultures. CR cultures therefore represent a pre-clinical lung cancer model for future basic and translational studies. View Publication

The rising incidence of autoimmune diseases such as multiple sclerosis (MS) in developed countries might be due to a more hygienic environment,particularly during early life. To investigate this concept,we developed a model of neonatal exposure to a common pathogen-associated molecular pattern,LPS,and determined its impact on experimental autoimmune encephalomyelitis (EAE). Mice exposed to LPS at 2 wk of age showed a delayed onset and diminished severity of myelin oligodendrocyte glycoprotein (MOG)-induced EAE,induced at 12 wk,compared with vehicle-exposed animals. Spinal cord transcript levels of CD3epsilon and F4/80 were lower in LPS- compared with PBS-exposed EAE animals with increased IL-10 levels in the LPS-exposed group. Splenic CD11c(+) cells from LPS-exposed animals exhibited reduced MHC class II and CD83 expression but increased levels of CD80 and CD86 both before and during EAE. MOG-treated APC from LPS-exposed animals stimulated less T lymphocyte proliferation but increased expansion of CD4(+)FoxP3(+) T cells compared with APC from PBS-exposed animals. Neuropathological studies disclosed reduced myelin and axonal loss in spinal cords from LPS-exposed compared with PBS-exposed animals with EAE,and this neuroprotective effect was associated with an increased number of CD3(+)FoxP3(+) immunoreactive cells. Analyses of human brain tissue revealed that FoxP3 expression was detected in lymphocytes,albeit reduced in MS compared with non-MS patients' brains. These findings support the concept of early-life microbial exposure influencing the generation of neuroprotective regulatory T cells and may provide insights into new immunotherapeutic strategies for MS. View Publication

Pluripotent stem cells,both human embryonic stem cells (hESC) and human-induced pluripotent stem cells (hiPSC),can give rise to multiple cell types and hence have tremendous potential for regenerative therapies. However,the tumorigenic potential of these cells remains a great concern,as reflected in the formation of teratomas by transplanted pluripotent cells. In clinical practice,most pluripotent cells will be differentiated into useful therapeutic cell types such as neuronal,cardiac,or endothelial cells prior to human transplantation,drastically reducing their tumorigenic potential. Our work investigated the extent to which these differentiated stem cell derivatives are truly devoid of oncogenic potential. In this study,we analyzed the gene expression patterns from three sets of hiPSC- and hESC-derivatives and the corresponding primary cells,and compared their transcriptomes with those of five different types of cancer. Our analysis revealed a significant gene expression overlap of the hiPSC- and hESC-derivatives with cancer,whereas the corresponding primary cells showed minimum overlap. Real-time quantitative PCR analysis of a set of cancer-related genes (selected on the basis of rigorous functional and pathway analyses) confirmed our results. Overall,our findings suggested that pluripotent stem cell derivatives may still bear oncogenic properties even after differentiation,and additional stringent functional assays to purify these cells should be done before they can be used for regenerative therapy. View Publication

Purpose: We determined whether elimination of CD105+ cells in the tumor microenvironment (TME) with anti-CD105 antibodies enhanced anti-disialoganglioside (GD2) antibody dinutuximab therapy of neuroblastoma when combined with activated natural killer (aNK) cells.Experimental Design: The effect of MSCs and monocytes on antibody-dependent cellular cytotoxicity (ADCC) mediated by dinutuximab with aNK cells against neuroblastoma cells was determined in vitro. ADCC with anti-CD105 mAb TRC105 and aNK cells against MSCs,monocytes,and endothelial cells,which express CD105,was evaluated. Anti-neuroblastoma activity in immunodeficient NSG mice of dinutuximab with aNK cells without or with anti-CD105 mAbs was determined using neuroblastoma cell lines and a patient-derived xenograft.Results: ADCC mediated by dinutuximab with aNK cells against neuroblastoma cells in vitro was suppressed by addition of MSCs and monocytes,and dinutuximab with aNK cells was less effective against neuroblastomas formed with coinjected MSCs and monocytes in NSG mice than against those formed by tumor cells alone. Anti-CD105 antibody TRC105 with aNK cells mediated ADCC against MSCs,monocytes,and endothelial cells. Neuroblastomas formed in NSG mice by two neuroblastoma cell lines or a patient-derived xenograft coinjected with MSCs and monocytes were most effectively treated with dinutuximab and aNK cells when anti-human (TRC105) and anti-mouse (M1043) CD105 antibodies were added,which depleted human MSCs and murine endothelial cells and macrophages from the TME.Conclusions: Immunotherapy of neuroblastoma with anti-GD2 antibody dinutuximab and aNK cells is suppressed by CD105+ cells in the TME,but suppression is overcome by adding anti-CD105 antibodies to eliminate CD105+ cells. View Publication

Transfer of therapeutic genes to human hematopoietic stem cells (HSCs) using complex vectors at clinically relevant efficiencies remains a major challenge. Recently we described a stable retroviral vector that sustains long-term expression of green fluorescent protein (GFP) and a human beta-globin gene in the erythroid progeny of transduced murine HSCs. We now report the efficient transduction of primitive human CD34(+) fetal liver or cord blood cells with this vector and expression of the beta-globin transgene in the erythroid progeny of these human cells for at least 2 months. After growth factor prestimulation and then a 2- to 3-day exposure to the virus,35% to 55% GFP(+) progeny were seen in assays of transduced colony-forming cells,primitive erythroid precursors that generate large numbers of glycophorin A(+) cells in 3-week suspension cultures,and 6-week long-term culture-initiating cells. In immunodeficient mice injected with unselected infected cells,5% to 15% of the human cells regenerated in the marrow (including the erythroid cells) were GFP(+) 3 and 6 weeks after transplantation. Importantly,the numbers of GFP(+) human lymphoid and either granulopoietic or erythroid cells in individual mice 6 weeks after transplantation were significantly correlated,indicative of the initial transduction of human multipotent cells with in vivo repopulating activity. Expression of the transduced beta-globin gene in human cells obtained directly from the mice or after their differentiation into erythroid cells in vitro was demonstrated by reverse transcriptase-polymerase chain reaction using specific primers. These experiments represent a significant step toward the realization of a gene therapy approach for human beta-globin gene disorders. View Publication

Mesenchymal stem cells (MSCs) have a high potential for therapeutic efficacy in treating diverse musculoskeletal injuries and cardiovascular diseases,and for ameliorating the severity of graft-versus-host and autoimmune diseases. While most of these clinical applications require substantial cell quantities,the number of MSCs that can be obtained initially from a single donor is limited. Reports on the derivation of MSC-like cells from pluripotent stem cells (PSCs) are,thus,of interest,as the infinite proliferative capacity of PSCs opens the possibility to generate large amounts of uniform batches of MSCs. However,characterization of such MSC-like cells is currently inadequate,especially with regard to the question of whether these cells are equivalent or identical to MSCs. In this study,we have derived MSC-like cells [induced PSC-derived MSC-like progenitor cells (iMPCs)] using four different methodologies from a newly established induced PSC line reprogrammed from human bone marrow stromal cells (BMSCs),and compared the iMPCs directly with the originating parental BMSCs. The iMPCs exhibited typical MSC/fibroblastic morphology and MSC-typical surface marker profile,and they were capable of differentiation in vitro along the osteogenic,chondrogenic,and adipogenic lineages. However,compared with the parental BMSCs,iMPCs displayed a unique expression pattern of mesenchymal and pluripotency genes and were less responsive to traditional BMSC differentiation protocols. We,therefore,conclude that iMPCs generated from PSCs via spontaneous differentiation represent a distinct population of cells which exhibit MSC-like characteristics. View Publication

Small intestinal CD103(+) dendritic cells (DCs) have the selective ability to promote de novo generation of regulatory T cells via the production of retinoic acid (RA). Considering that aldehyde dehydrogenase (ALDH) activity controls the production of RA,we used a flow cytometry-based assay to measure ALDH activity at the single-cell level and to perform a comprehensive analysis of the RA-producing DC populations present in lymphoid and nonlymphoid mouse tissues. RA-producing DCs were primarily of the tissue-derived,migratory DC subtype and can be readily found in the skin and in the lungs as well as in their corresponding draining lymph nodes. The RA-producing skin-derived DCs were capable of triggering the generation of regulatory T cells,a finding demonstrating that the presence of RA-producing,tolerogenic DCs is not restricted to the intestinal tract as previously thought. Unexpectedly,the production of RA by skin DCs was restricted to CD103(-) DCs,indicating that CD103 expression does not constitute a universal" marker for RA-producing mouse DCs. Finally� View Publication

Human embryonic stem cells (hESCs) and their differentiated progeny allow for investigation of important changes/events during normal embryonic development. Currently most of the research is focused on proteinacous changes occurring as a result of differentiation of stem cells and little is known about changes in cell surface glycosylation patterns. Identification of cell lineage specific glycans can help in understanding their role in maintenance,proliferation and differentiation. Furthermore,these glycans can serve as markers for isolation of homogenous populations of cells. Using a panel of eight biotinylated lectins,the glycan expression of hESCs,hESCs-derived human neural progenitors (hNP) cells,and hESCs-derived mesenchymal progenitor (hMP) cells was investigated. Our goal was to identify glycans that are unique for hNP cells and use the corresponding lectins for cell isolation. Flow cytometry and immunocytochemistry were used to determine expression and localization of glycans,respectively,in each cell type. These results show that the glycan expression changes upon differentiation of hESCs and is different for neural and mesenchymal lineage. For example,binding of PHA-L lectin is low in hESCs (14±4.4%) but significantly higher in differentiated hNP cells (99±0.4%) and hMP cells (90±3%). Three lectins: VVA,DBA and LTL have low binding in hESCs and hMP cells,but significantly higher binding in hNP cells. Finally,VVA lectin binding was used to isolate hNP cells from a mixed population of hESCs,hNP cells and hMP cells. This is the first report that compares glycan expression across these human stem cell lineages and identifies significant differences. Also,this is the first study that uses VVA lectin for isolation for human neural progenitor cells. View Publication

BACKGROUND Glioblastoma (GBM) is the most common and aggressive form of primary brain tumor. Although numerous postoperative therapeutic strategies have already been developed,including radiotherapy,tumors inevitably recur after several years of treatment. The coinhibitory molecule B7-H4 negatively regulates T cell immune responses and promotes immune escape. Exosomes mediate intercellular communication and initiate immune evasion in the tumor microenvironment (TME). OBJECTIVE This study aimed to determine whether B7-H4 is upregulated by radiation and loaded into exosomes,thus contributing to immunosuppression and enhancing tumor growth. METHODS Iodixanol density-gradient centrifugation and flow cytometry were used to verify exosomal B7-H4. Na{\{i}}ve T cells were differentiated into Th1 cells with or without exosomes. T cell-secreted cytokines and markers of T cell subsets were measured. Mechanistically the roles of B7-H4 and ALIX in GBM were analyzed using databases and tissue samples. Co-immunoprecipitation and pull-down assays were used to tested the direct interactions between ATM and ALIX or STAT3. In vitro ATM kinase assays western blotting and site-directed mutation were used to assess ATM-mediated STAT3 phosphorylation. Finally the contribution of exosomal B7-H4 to immunosuppression and tumor growth was investigated in vivo. RESULTS Exosomes from irradiated GBM cells decreased the anti-tumor immune response of T cell in vitro and in vivo via delivered B7-H4. Mechanistically irradiation promoted exosome biogenesis by increasing the ATM-ALIX interaction. Furthermore the ATM-phosphorylated STAT3 was found to directly binds to the B7-H4 promoter to increase its expression. Finally the radiation-induced increase in exosomal B7-H4 induced FoxP3 expression during Th1 cell differentiation via the activated STAT1 pathway. In vivo exosomal B7-H4 decreased the radiation sensitivity of GBM cells and reduced the survival of GBM mice model. CONCLUSION This study showed that radiation-enhanced exosomal B7-H4 promoted immunosuppression and tumor growth hence defining a direct link between irradiation and anti-tumor immune responses. Our results suggest that co-administration of radiotherapy with anti-B7-H4 therapy could improve local tumor control and identify exosomal B7-H4 as a potential tumor biomarker." View Publication

One important function of endothelial cells in glioblastoma multiforme (GBM) is to create a niche that helps promote self-renewal of cancer stem-like cells (CSLC). However,the underlying molecular mechanism for this endothelial function is not known. Since activation of NOTCH signaling has been found to be required for propagation of GBM CSLCs,we hypothesized that the GBM endothelium may provide the source of NOTCH ligands. Here,we report a corroboration of this concept with a demonstration that NOTCH ligands are expressed in endothelial cells adjacent to NESTIN and NOTCH receptor-positive cancer cells in primary GBMs. Coculturing human brain microvascular endothelial cells (hBMEC) or NOTCH ligand with GBM neurospheres promoted GBM cell growth and increased CSLC self-renewal. Notably,RNAi-mediated knockdown of NOTCH ligands in hBMECs abrogated their ability to induce CSLC self-renewal and GBM tumor growth,both in vitro and in vivo. Thus,our findings establish that NOTCH activation in GBM CSLCs is driven by juxtacrine signaling between tumor cells and their surrounding endothelial cells in the tumor microenvironment,suggesting that targeting both CSLCs and their niche may provide a novel strategy to deplete CSLCs and improve GBM treatment. View Publication

Availability of tumor and non-tumor patient-derived models would promote the development of more effective therapeutics for non-small cell lung cancer (NSCLC). Recently,conditionally reprogrammed cells (CRC) methodology demonstrated exceptional potential for the expansion of epithelial cells from patient tissues. However,the possibility to expand patient-derived lung cancer cells using CRC protocols is controversial. Here,we used CRC approach to expand cells from non-tumoral and tumor biopsies of patients with primary or metastatic NSCLC as well as pulmonary metastases of colorectal or breast cancers. CRC cultures were obtained from both tumor and non-malignant tissues with extraordinary high efficiency. Tumor cells were tracked in vitro through tumorigenicity assay,monitoring of tumor-specific genetic alterations and marker expression. Cultures were composed of EpCAM+ lung epithelial cells lacking tumorigenic potential. NSCLC biopsies-derived cultures rapidly lost patient-specific genetic mutations or tumor antigens. Similarly,pulmonary metastases of colon or breast cancer generated CRC cultures of lung epithelial cells. All CRC cultures examined displayed epithelial lung stem cell phenotype and function. In contrast,brain metastatic lung cancer biopsies failed to generate CRC cultures. In conclusion,patient-derived primary and metastatic lung cancer cells were negatively selected under CRC conditions,limiting the expansion to non-malignant lung epithelial stem cells from either tumor or non-tumor tissue sources. Thus,CRC approach cannot be applied for direct therapeutic testing of patient lung tumor cells,as the tumor-derived CRC cultures are composed of (non-tumoral) airway basal cells. View Publication

The identification and targeted therapy of cells involved in hepatocellular carcinoma (HCC) recurrence remain challenging. Here,we generated a monoclonal antibody against recurrent HCC,1B50-1,that bound the isoform 5 of the α2δ1 subunit of voltage-gated calcium channels and identified a subset of tumor-initiating cells (TICs) with stem cell-like properties. A surgical margin with cells detected by 1B50-1 predicted rapid recurrence. Furthermore,1B50-1 had a therapeutic effect on HCC engraftments by eliminating TICs. Finally,α2δ1 knockdown reduced self-renewal and tumor formation capacities and induced apoptosis of TICs,whereas its overexpression led to enhanced sphere formation,which is regulated by calcium influx. Thus,α2δ1 is a functional liver TIC marker,and its inhibitors may serve as potential anti-HCC drugs. View Publication