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

In preclinical studies on the T-cell engager MP0533,the authors show that targeting multiple tumor-associated antigens may lead to better selectivity and efficacy in eliminating leukemic stem cells and blasts,representing a promising therapeutic strategy for AML. View Publication

Head and neck squamous cell carcinoma (HNSCC) is a highly malignant disease,and death rates have remained at approximately 50% for decades. New tumor-targeting strategies are desperately needed,and a previous report indicated the triggered differentiation of HPV-negative HNSCC cells to confer therapeutic benefits. Using patient-derived tumor cells,we created a similar HNSCC differentiation model of HPV+ tumor cells from two patients. We observed a loss of malignant characteristics in differentiating cell culture conditions,including irregularly enlarged cell morphology,cell cycle arrest with downregulation of Ki67,and reduced cell viability. RNA-Seq showed myocyte-like differentiation with upregulation of markers of myofibril assembly. Immunofluorescence staining of differentiated and undifferentiated primary HPV+ HNSCC cells confirmed an upregulation of these markers and the formation of parallel actin fibers reminiscent of myoblast-lineage cells. Moreover,immunofluorescence of HPV+ tumor tissue revealed areas of cells co-expressing the identified markers of myofibril assembly,HPV surrogate marker p16,and stress-associated basal keratinocyte marker KRT17,indicating that the observed myocyte-like in vitro differentiation occurs in human tissue. We are the first to report that carcinoma cells can undergo a triggered myocyte-like differentiation,and our study suggests that the targeted differentiation of HPV+ HNSCCs might be therapeutically valuable. Subject terms: Oral cancer,Mechanisms of disease,Cell death View Publication

Both antitumor and protumor property of mesenchymal stem cells (MSCs) have been demonstrated. We hypothesize that this contradiction is due to the heterogeneity of MSC subsets and that extracellular vesicles (EVs) from distinct MSC subsets can transfer the corresponding antitumor activities. Here we evaluated the antitumor activities of two subsets of adipose-derived mesenchymal stem cells (ADSCs) and ADSC-derived EVs (ADSC-EVs) in immunocompetent syngeneic mouse models of breast cancer. We identified CD90high and CD90low ADSC subsets and demonstrated that CD90high ADSCs could be converted into CD90low ADSCs by stimulation with LPS. CD90low ADSCs and its derived EVs significantly inhibited tumor growth in tumor-bearing mice. Benefit of tumor control were associated with decreased tumor cell proliferation and migration,and enhanced tumor cell apoptosis mediated by ADSC-EVs. Antioncogenic miRNA-16-5p loaded CD90low ADSC-EVs further significantly enhanced antitumor activities. Taken together,this study represents the first attempt to apply our newly identified antitumor ADSCs and its derived EVs in preclinical treatment of breast cancer. This study also provides the evidence that EVs can serve as a novel and effective therapeutics or drug delivery vesicle. This new therapeutic approach could be potentially applicable to breast cancer and many other types of cancer. View Publication

Overcoming drug resistance and targeting cancer stem cells remain challenges for curative cancer treatment. To investigate the role of miRNAs in regulating drug resistance and leukemic stem cell (LSCs) fate,we performed global transcriptome profiling in treatment-na{\{i}}ve chronic myeloid leukemia (CML) stem/progenitor cells and identified that miR-185 levels anticipate their response to ABL tyrosine kinase inhibitors (TKIs). miR-185 functions as a tumor suppressor; its restored expression impaired survival of drug-resistant cells sensitized them to TKIs in vitro and markedly eliminated long-term repopulating LSCs and infiltrating blast cells conferring a survival advantage in pre-clinical xenotransplantation models. Integrative analysis with mRNA profiles uncovered PAK6 as a crucial target of miR-185 and pharmacological inhibition of PAK6 perturbed the RAS/MAPK pathway and mitochondrial activity sensitizing therapy-resistant cells to TKIs. Thus miR-185 presents as a potential predictive biomarker and dual targeting of miR-185-mediated PAK6 activity and BCR-ABL may provide a valuable strategy for overcoming drug resistance in patients." View Publication

Aim To analyse the ability of mesenchymal stem cells (MSCs) to regulate interleukin 6 (IL-6) and transforming growth factor (TGF-$\beta$) expression in vitro under co-culture conditions in human systemic lupus erythematosus (SLE). Method This study used a post-test group design that used peripheral blood mononuclear cells (PBMCs) from SLE patients at Kariadi Hospital,Semarang,Indonesia,and MSCs from a human umbilical cord. The cells were divided into two groups. The control group of PBMCs was treated with a standard medium,and the treatment group was co-cultured with the MSCs at a 1:40 ratio. Following 24 h incubation,the levels of IL-6 and TGF-$\beta$ released in the culture medium were measured using a specific ELISA assay. Results This study showed a significant decrease in IL-6 level (p{\textless}0.05) and a significant increase in TGF-$\beta$ level (p{\textless}0.001) following 24 h of co-culture incubation of human SLE PBMCs cells and MSCs. Conclusion The PBMCs-to-MSCs ratio of 1:40 can regulate the IL-6 and TGF-$\beta$ levels in human SLE PBMCs. View Publication

Human pluripotent stem cells including induced pluripotent stem cells (iPSCs) and embryonic stem cells hold great promise for cell-based therapies,but safety concerns that complicate consideration for routine clinical use remain. Installing a safety switch" based on the inducible caspase-9 (iCASP9) suicide gene system should offer added control over undesirable cell replication or activity. Previous studies utilized lentiviral vectors to integrate the iCASP9 system into T cells and iPSCs. This method results in random genomic insertion of the suicide switch and inefficient killing of the cells after the switch is "turned on" with a small molecule (eg AP1903). To improve the safety and efficiency of the iCASP9 system for use in iPSC-based therapy we precisely installed the system into a genomic safe harbor the AAVS1 locus in the PPP1R12C gene. We then evaluated the efficiencies of different promoters to drive iCASP9 expression in human iPSCs. We report that the commonly used EF1$\alpha$ promoter is silenced in iPSCs and that the endogenous promoter of the PPP1R12C gene is not strong enough to drive high levels of iCASP9 expression. However the CAG promoter induces strong and stable iCASP9 expression in iPSCs and activation of this system with AP1903 leads to rapid killing and complete elimination of iPSCs and their derivatives including MSCs and chondrocytes in vitro. Furthermore iPSC-derived teratomas shrank dramatically or were completely eliminated after administration of AP1903 in mice. Our data suggest significant improvements on existing iCASP9 suicide switch technologies and may serve as a guide to other groups seeking to improve the safety of stem cell-based therapies." View Publication

We examined the potential role of myosin and actin in the release of human immunodeficiency virus type 1 (HIV-1) from infected cells. Wortmannin (100 nM to 5 microM),an effective inhibitor of myosin light chain kinase,blocked the release of HIV-1 from infected T-lymphoblastoid and monocytoid cells in a concentration-dependent manner. Cytochalasin D,a reagent that disrupts the equilibrium between monomeric and polymeric actin,also partially inhibited the release of HIV-1 from the infected cells. At the budding stage,myosin and HIV-1 protein were detected in the same areas on the plasma membrane by using dual-label immunofluorescence microscopy and immunoelectron microscopy. In the presence of 5 microM wortmannin,viral components were observed on the plasma membrane by using immunofluorescence microscopy and electron microscopy,implying that wortmannin did not disturb the transport of viral proteins to the plasma membrane but rather inhibited budding. View Publication

Francisella tularensis (Ft),a Gram-negative bacterium that causes tularemia,possesses a non-inflammatory atypical LPS (LPSFt) that is highly immunogenic through unknown mechanism. We previously showed that immunization with LPSFt,a type 2 T-independent (TI) antigen,elicits protective LPSFt-specific IgM (IgMFt) and IgG3Ft by B1 cells in a mechanism dependent on the IL-5 produced by innate lymphoid cells type 2 (ILC2). Here,we examined the role of complement in the B1 cells’ response against LPSFt. C3-/-,C1q-/- and C4-/- mice immunized with LPSFt failed to produce IgMFt and IgG3Ft. In contrast,the response of Cfb-/- and Mbl1/Mbl2-/- mice was comparable to that of WT mice. Thus,activation of the classical complement cascade,but not the alternative or the Mannose Binding Lectin pathway,is required for activation of B1 cells and production of LPSFt-specific antibodies. Complement activation generates the C3d fragment,which opsonizes antigens for recognition by complement receptor-2 (CR2),and the C3a and C5a anaphylatoxins. Our results show that C3d opsonized LPSFt and that the response to immunization was dependent on CR2 expression by B1 cells. Importantly,the response to LPSFt immunization was also drastically decreased in C3ar1-/-,but not in C5ar1-/- mice. C3a induced IL-5 in ILC2,which supported B1 cells activation. Decreased antibody production in C3ar1-/- and Cr2-/- mice correlated with increased susceptibility to tularemia. Together,these results demonstrate that the high immunogenicity of LPSFt depends on two effector mechanisms triggered by activation of the classical complement pathway: 1) tagging of LPSFt with C3d fragment,leading to its interaction with CR2 expressed by B1 cells; 2) production of the anaphylatoxin C3a that stimulated IL-5 secretion by ILC2. Our study increases our understanding of the B1 cells’ response to TI-2 antigens and identifies two complement effector mechanisms that can be harnessed for therapeutic interventions. Author summaryThe lipopolysaccharide (LPS) of the bacterium Francisella tularensis strongly stimulates B cells for antibody production independently of T cell help through unknown mechanism. In the present study we examined the role of the complement cascade in this process. We found that production of antibodies against this LPS depends on activation of the classical complement pathway but not the MBL-dependent lectin or the alternative pathways. Following complement activation,LPS became tagged with the C3d complement fragment leading to its interaction with the complement receptor CR2 expressed by B cells. Complement activation also resulted in production of the anaphylatoxin C3a that was required for B cells activation,possibly through induction of IL-5 by innate lymphoid cells 2. Our study increases our understanding of the B cells’ response to T-independent antigens and identifies two complement effector mechanisms that can be harnessed for therapeutic interventions. View Publication

The small cytokine-inducible SH2 domain-containing protein (CIS) has been implicated in the negative regulation of signaling through cytokine receptors. CIS reduces growth of erythropoietin receptor (EpoR)-dependent cell lines,but its role in proliferation,differentiation,and survival of erythroid progenitor cells has not been resolved. To dissect the function of CIS in cell lines and erythroid progenitor cells,we generated green fluorescent protein (GFP)-tagged versions of wild type CIS,a mutant harboring an inactivated SH2 domain (CIS R107K),and a mutant with a deletion of the SOCS Box (CISDeltaBox). Retroviral expression of the GFP fusion proteins in BaF3-EpoR cells revealed that both Tyr-401 in the EpoR and an intact SH2 domain within CIS are prerequisites for receptor recruitment. As a consequence,both are essential for the growth inhibitory effect of CIS,whereas the CIS SOCS box is dispensable. Accordingly,the retroviral expression of GFP-CIS but not GFP-CIS R107K impaired proliferation of erythroid progenitor cells in colony assays. Erythroid differentiation was unaffected by either protein. Interestingly,apoptosis of erythroid progenitor cells was increased upon GFP-CIS expression and this required the presence both of an intact SH2 domain and the SOCS box. Thus,CIS negatively regulates signaling at two levels,apoptosis and proliferation,and thereby sets a threshold for signal transduction. View Publication

Lymphocyte activation is regulated by costimulatory and inhibitory receptors,of which both B and T lymphocyte attenuator (BTLA) and CD160 engage herpesvirus entry mediator (HVEM). Notably,it remains unclear how HVEM functions with each of its ligands during immune responses. In this study,we show that HVEM specifically activates CD160 on effector NK cells challenged with virus-infected cells. Human CD56(dim) NK cells were costimulated specifically by HVEM but not by other receptors that share the HVEM ligands LIGHT,Lymphotoxin-α,or BTLA. HVEM enhanced human NK cell activation by type I IFN and IL-2,resulting in increased IFN-γ and TNF-α secretion,and tumor cell-expressed HVEM activated CD160 in a human NK cell line,causing rapid hyperphosphorylation of serine kinases ERK1/2 and AKT and enhanced cytolysis of target cells. In contrast,HVEM activation of BTLA reduced cytolysis of target cells. Together,our results demonstrate that HVEM functions as a regulator of immune function that activates NK cells via CD160 and limits lymphocyte-induced inflammation via association with BTLA. View Publication

Two monoclonal antibodies,BA16 and BA17,have been developed using a detergent-insoluble extract of human mammary epithelial organoids as immunogen. Indirect immunofluorescent staining of cultured cells showed that the component reacting with the antibodies was filamentous and the intensity of staining was stronger in mitotic cells. Immunoblotting of cell extracts showed that both antibodies react with only one band of 40 X 10(3) molecular weight,which was present in keratin-enriched extracts of cells or organoids. Furthermore,the tissue distribution of the component reacting with the antibodies was that predicted for human keratin 19. The antibodies showed differences in the intensity of staining of cells or tissue sections fixed and prepared in different ways indicating that they reacted with different epitopes. The pattern of expression of the 40 X 10(3) Mr keratin by normal mammary epithelial cells was investigated by immunoperoxidase staining of tissue sections,cultured milk cells,and organoids of different sizes cultured in collagen gels. It was found that basal or myoepithelial cells did not express this keratin. Some heterogeneity of expression of this component was seen in luminal epithelial cells,found almost exclusively in the smaller structures. These cells did,however,express other keratins characteristic of luminal cells. The distribution in the mammary tree of the luminal cells that did not express the 40 X 10(3) Mr keratin appears to be similar to that expected for cells with the proliferative potential to produce new terminal ductal lobular units or an increase in branching of existing terminal ductal lobular units. It is shown that these cells have considerable proliferative potential by the fact that they form large colonies in milk cell cultures. View Publication