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

SummaryInterleukin-33 (IL-33) is an immunoregulatory cytokine that moderately suppresses experimental autoimmune encephalomyelitis (EAE),a murine model of multiple sclerosis (MS). However,poor pharmacokinetics and toxicity hinder its clinical translation. To address these limitations,we develop an activity-attenuated IL-33 by recombinant fusion to serum albumin (SA). SA-IL-33 exhibits reduced toxicity and prolonged residence in the secondary lymphoid organs (SLOs),sites of T cell priming in autoimmunity,compared to wild-type (WT) IL-33. Prophylactic SA-IL-33 administration prevents EAE with superior efficacy to WT IL-33 and comparable efficacy to fingolimod (FTY720),a Food and Drug Administration (FDA)-approved MS drug. Therapeutic SA-IL-33 treatment also reduces disease severity in both chronic and relapsing-remitting EAE. SA-IL-33 modulates immunity in EAE by suppressing CD45+ cell infiltration (including myelin-reactive T helper 17 [TH17] cells) in the spinal cord,while expanding type 2 immune cells (including type 2 innate lymphoid cells [ILC2s],ST2+ regulatory T cells [Tregs],T helper 2 [TH2] cells,and M2-polarized macrophages) in the SLOs. These findings suggest that SA-IL-33 is a promising therapeutic for neuroinflammatory diseases. Graphical abstract Highlights•Fusion of serum albumin (SA) to interleukin-33 (IL-33) attenuates its activity and toxicity•Engineered SA-IL-33 exhibits prolonged residence in the secondary lymphoid organs (SLOs)•SA-IL-33 treatment both prevents the onset of and reduces established neuroinflammation in mice•Cytokine therapy suppresses TH17 cells in the CNS and promotes immunoregulation in the SLOs The clinical utility of interleukin-33 is hindered by poor pharmacokinetics and toxicity. Budina et al. develop a fusion of serum albumin and interleukin-33 (SA-IL-33) with reduced toxicity and prolonged lymph node residence. SA-IL-33 prevents the onset of and suppresses established inflammation-mediated paralysis in mice,demonstrating promise as a therapeutic for neuroinflammatory diseases. View Publication

Successful cell and gene therapy clinical trials have resulted in the US Food and Drug Administration and European Medicines Agency approving their use for treatment of patients with certain types of cancers and monogenetic diseases. These novel therapies,which rely heavily on lentiviral vectors to deliver therapeutic transgenes to patient cells,have driven additional investigations,increasing demand for both pre-clinical and current Good Manufacturing Practices-grade viral vectors. To better support novel studies by improving current production methods,we report the development of a genetically modified HEK293T-based cell line that is null for expression of both Protein Kinase R and Beta-2 microglobulin and grows in suspension using serum-free media,SJ293TS-DPB. Absence of Protein Kinase R increased anti-sense lentiviral vector titers by more than 7-fold,while absence of Beta-2 microglobulin,a key component of major histocompatibility complex class I molecules,has been reported to reduce the immunogenicity of lentiviral particles. Furthermore,we describe an improved methodology for culturing SJ293TS-DPB that facilitates expansion,reduces handling,and increases titers by 2-fold compared with previous methods. SJ293TS-DPB stably produced lentiviral vectors for over 4 months and generated lentiviral vectors that efficiently transduce healthy human donor T cells and CD34 + hematopoietic stem cells. View Publication

In recent years,the differentiation of bone marrow cells (BMCs) into myocytes has been extensively investigated,but the findings remain inconclusive. The purpose of this study was to determine the conditions necessary to induce myogenic differentiation in short-term cultures of adult BMCs,and to identify the BMC subpopulation responsible for this phenomenon. We report that high-density cultures of murine hematopoietic BMCs gave rise to spontaneous beating cell clusters in the presence of vascular endothelial and fibroblast growth factors. These clusters originated from c-kit(pos) cells. The formation of the clusters could be completely blocked by adding a c-kit/tyrosine kinase inhibitor,Gleevec (imatinib mesylate; Novartis International,Basel,Switzerland,http://www.novartis.com),to the culture. Cluster formation was also blunted in BMCs from c-kit-deficient (Kit(W)/Kit(W-v)) mice. Clustered cells expressed cardiomyocyte-specific transcription factor genes Gata-4 and Nkx2.5,sarcomeric proteins beta-MHC and MLC-2v,and ANF and connexin-43. Immunostaining revealed alpha-sarcomeric actinin expression in more than 90% of clustered cells. Under electron microscopy,the clustered cells exhibited a sarcomeric myofiber arrangement and z-bands. This study defines the microenvironment required to achieve a reproducible in vitro model of beating,myogenic cell clusters. This model could be used to examine the mechanisms responsible for the postnatal myogenic differentiation of BMCs. Our results identify c-kit(pos) bone marrow hematopoietic cells as the source of the myogenic clusters. View Publication

Definitive hematopoietic stem and progenitor cells (HSCs/Ps) originating from the yolk sac and/or para-aorta-splanchno-pleura/aorta-gonad-mesonephros are hypothesized to colonize the fetal liver,but mechanisms involved are poorly defined. The Rac subfamily of Rho GTPases has been shown to play essential roles in HSC/P localization to the bone marrow following transplantation. Here,we study the role of Rac1 in HSC/P migration during ontogeny and seeding of fetal liver. Using a triple-transgenic approach,we have deleted Rac1 in HSCs/Ps during very early embryonic development. Without Rac1,there was a decrease in circulating HSCs/Ps in the blood of embryonic day (E) 10.5 embryos,while yolk sac definitive hematopoiesis was quantitatively normal. Intraembryonic hematopoiesis was significantly impaired in Rac1-deficient embryos,culminating with absence of intra-aortic clusters and fetal liver hematopoiesis. At E10.5,Rac1-deficient HSCs/Ps displayed decreased transwell migration and impaired inter-action with the microenvironment in migration-dependent assays. These data suggest that Rac1 plays an important role in HSC/P migration during embryonic development and is essential for the emergence of intraembryonic hematopoiesis. View Publication

This study aimed to assess the efficacy of Quality and Quantity media-cultured mononuclear cells (QQ-MNCs) for promoting nerve regeneration in a mouse sciatic nerve transection model. Human peripheral blood mononuclear cells (PB-MNCs) and QQ-MNCs derived from healthy volunteers were used/compared. The left sciatic nerve was surgically transected in 27 mice. After complete nerve transection was confirmed,end-to-end direct epineurial nerve repair was performed using 9–0 nylon. Fibrin glue was applied to the tissue around the injury site to limit diffusion of the study treatment followed by application of 0.5 ml phosphate buffered saline (PBS) or PB-MNCs (2x10 6 cells) or QQ-MNCs (2x10 6 cells) to the injury site. The skin was then closed using 6–0 nylon. Histomorphology,immunohistochemistry,electrophysiologic examination,and functional assessment were evaluated at 12-weeks followed by euthanasia and subsequent harvesting of the left sciatic nerves and the left and right gastrocnemius muscles for examination. QQ-MNCs mice exhibited significant improvement in all histomorphologic parameters (axon fiber diameter,myelin thickness,percentage of nerve density) and immunohistochemistry assays (S100,SOX10,GFAP,neurofilament,IL-1β,VEGF,anti-HNA,TNF-α,vWF) compared to PBS mice (all p < 0.05). QQ-MNCs mice also had a significantly higher Basso Mouse Scale score compared to PBS mice ( p = 0.018). The percentage of nerve density adjacent to the injury site was significantly higher in QQ-MNCs mice than in PB-MNCs mice ( p = 0.049). IL-1β expression was significantly lower in QQ-MNCs mice than in PB-MNCs mice ( p = 0.01). QQ-MNCs mice demonstrated significantly better functional and histomorphologic outcomes of nerve regeneration compared to PB-MNCs mice and PBS mice. View Publication

Mouse embryonic stem (mES) cells have short duration of their cell cycle and are capable of proliferating in the absence of growth factors. To find out which signaling pathways contribute to the regulation of the mES cell cycle,we used pharmacological inhibitors of MAP and PI3 kinase cascades. The MAP kinase inhibitors as well as serum withdrawal did not affect mES cell cycle distribution,whereas the inhibitor of PI3K activity,LY294002,induced accumulation of cells in G(1) phase followed by apoptotic cell death. Serum withdrawal also causes apoptosis,but it does not change the content and activity of cell cycle regulators. In contrast,in mES cells treated with LY294002,the activities of Cdk2 and E2F were significantly decreased. Interestingly,LY294002had a much stronger effect on cell cycle distribution in low serum conditions,implying that serum can promote G(1)--textgreaterS transition of mES cells by a LY294002-resistant mechanism. Thus,proliferation of mES cells is maintained by at least two separate mechanisms: a LY294002-sensitive pathway,which is active even in the absence of serum,and LY294002-resistant,but serum-dependent,pathway. View Publication

OBJECTIVES Kidney disease is emerging as a critical medical problem worldwide. Because of limited treatment options for the damaged kidney,stem cell treatment is becoming an alternative therapeutic approach. Of many possible human stem cell sources,pluripotent stem cells are most attractive due to their self-renewal and pluripotent capacity. However,little is known about the derivation of renal lineage cells from human pluripotent stem cells (hPSCs). In this study,we developed a novel protocol for differentiation of nephron progenitor cells (NPCs) from hPSCs in a serum- and feeder-free system. MATERIALS AND METHODS We designed step-wise protocols for differentiation of human pluripotent stem cells toward primitive streak,intermediate mesoderm and NPCs by recapitulating normal nephrogenesis. Expression of key marker genes was examined by RT-PCR,real time RT-PCR and immunocytochemistry. Each experiment was independently performed three times to confirm its reproducibility. RESULTS After modification of culture period and concentration of exogenous factors,hPSCs can differentiate into NPCs that markedly express specific marker genes such as SIX2,GDNF,HOXD11,WT1 and CITED1 in addition to OSR1,PAX2,SALL1 and EYA1. Moreover,NPCs possess the potential of bidirectional differentiation into both renal tubular epithelial cells and glomerular podocytes in defined culture conditions. In particular,approximately 70% of SYN-positive cells were obtained from hPSC-derived NPCs after podocytes induction. NPCs can also form in vitro tubule-like structures in three dimensional culture systems. CONCLUSIONS Our novel protocol for hPSCs differentiation into NPCs can be useful for producing alternative sources of cell replacement therapy and disease modeling for human kidney diseases. View Publication