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

Clonal expansion of B cell chronic lymphocytic leukemia (B-CLL) occurs within lymphoid tissue pseudofollicles. IL-15,a stromal cell-associated cytokine found within spleens and lymph nodes of B-CLL patients,significantly boosts in vitro cycling of blood-derived B-CLL cells following CpG DNA priming. Both IL-15 and CpG DNA are elevated in microbe-draining lymphatic tissues,and unraveling the basis for IL-15-driven B-CLL growth could illuminate new therapeutic targets. Using CpG DNA-primed human B-CLL clones and approaches involving both immunofluorescent staining and pharmacologic inhibitors,we show that both PI3K/AKT and JAK/STAT5 pathways are activated and functionally important for IL-15→CD122/ɣc signaling in ODN-primed cells expressing activated pSTAT3. Furthermore,STAT5 activity must be sustained for continued cycling of CFSE-labeled B-CLL cells. Quantitative RT-PCR experiments with inhibitors of PI3K and STAT5 show that both contribute to IL-15-driven upregulation of mRNA for cyclin D2 and suppression of mRNA for DNA damage response mediators ATM,53BP1,and MDC1. Furthermore,protein levels of these DNA damage response molecules are reduced by IL-15,as indicated by Western blotting and immunofluorescent staining. Bioinformatics analysis of ENCODE chromatin immunoprecipitation sequencing data from cell lines provides insight into possible mechanisms for STAT5-mediated repression. Finally,pharmacologic inhibitors of JAKs and STAT5 significantly curtailed B-CLL cycling when added either early or late in a growth response. We discuss how the IL-15-induced changes in gene expression lead to rapid cycling and possibly enhanced mutagenesis. STAT5 inhibitors might be an effective modality for blocking B-CLL growth in patients. View Publication

IL-33,a new member of the IL-1 family,has been described as an important inducer of Th2 cytokines and mediator of inflammatory responses. In this study,we demonstrate that murine basophils sorted directly from the bone marrow,without prior exposure to IL-3 or Fc(epsilon)R cross-linking,respond to IL-33 alone by producing substantial amounts of histamine,IL-4,and IL-6. These cells express ST2 constitutively and generate a cytokine profile that differs from their IL-3-induced counterpart by a preferential production of IL-6. In vivo,IL-33 promotes basophil expansion in the bone marrow (BM) through an indirect mechanism of action depending on signaling through the beta(c) chain shared by receptors for IL-3,GM-CSF,and IL-5. IL-3 can still signal through its specific beta(IL-3) chain in these mutant mice,which implies that it is not the unique growth-promoting mediator in this setup,but requires IL-5 and/or GMCSF. Our results support a major role of the latter growth factor,which is readily generated by total BM cells as well as sorted basophils in response to IL-33 along with low amounts of IL-3. Furthermore,GM-CSF amplifies IL-3-induced differentiation of basophils from BM cells,whereas IL-5 that is also generated in vivo,affects neither their functions nor their growth in vitro or in vivo. In conclusion,our data provide the first evidence that IL-33 not only activates unprimed basophils directly,but also promotes their expansion in vivo through induction of GM-CSF and IL-3. View Publication

BACKGROUND Theoretically human embryonic stem cells (hESCs) have the capacity to self-renew and differentiate into all human cell types. Therefore,the greatest promise of hESCs-based therapy is to replace the damaged tissues of patients suffering from traumatic or degenerative diseases by the exact same type of cells derived from hESCs. Allograft immune rejection is one of the obstacles for hESCs-based clinical applications. Human leukocyte antigen (HLA) II leads to CD4(+) T cells-mediated allograft rejection. Hence,we focus on optimizing hESCs for clinic application through gene modification. RESULTS Transcription activator-like effector nucleases (TALENs) were used to target MHC class II transactivator (CIITA) in hESCs efficiently. CIITA (-/-) hESCs did not show any difference in the differentiation potential and self-renewal capacity. Dendritic cells (DCs) derived from CIITA (-/-) hESCs expressed CD83 and CD86 but without the constitutive HLA II. Fibroblasts derived from CIITA (-/-) hESCs were powerless in IFN-$\$ expression of HLA II. CONCLUSION We generated HLA II defected hESCs via deleting CIITA,a master regulator of constitutive and IFN-$\$ expression of HLA II genes. CIITA (-/-) hESCs can differentiate into tissue cells with non-HLA II expression. It's promising that CIITA (-/-) hESCs-derived cells could be used in cell therapy (e.g.,T cells and DCs) and escape the attack of receptors' CD4(+) T cells,which are the main effector cells of cellular immunity in allograft. View Publication