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41.
It has been recently that particulate matter (PM) exposure increases the risk and exacerbation of allergic asthma. However, the underlying mechanisms and factors associated with increased allergic responses remain elusive. We evaluated IL‐23 and IL‐23R (receptor) expression, as well as changes in the asthmatic phenotype in mice administered PM and a low dose of house dust mite (HDM). Next, changes in the phenotype and immune responses were evaluated after intranasal administration of anti‐IL‐23 antibody during co‐exposure to PM and low‐dose HDM. We also performed in vitro experiments to investigate the effect of IL‐23. IL‐23 expression was significantly increased in Epcam+CD45− and CD11c+ cells, while that of IL‐23R was increased in Epcam+CD45− cells only in mice administered PM and low‐dose HDM. Administration of anti‐IL‐23 antibody led to decreased airway hyperresponsiveness, eosinophils, and activation of dendritic cells, reduced populations of Th2 Th17, ILC2, the level of IL‐33 and granulocyte‐macrophage colony‐stimulating factor (GM‐CSF). Inhibition of IL‐23 in PM and low‐dose HDM stimulated airway epithelial cell line resulted in decreased IL‐33, GM‐CSF and affected ILC2 and the activation of BMDCs. PM augmented the phenotypes and immunologic responses of asthma even at low doses of HDM. Interestingly, IL‐23 affected immunological changes in airway epithelial cells. 相似文献
42.
Alan Tin Lun Lam Valerie Ho Svetlan Vassilev Shaul Reuveny Steve Kah Weng Oh 《Cell proliferation》2022,55(8)
ObjectivesInduced pluripotent stem cells (iPSCs) generated by monolayer cultures is plagued by low efficiencies, high levels of manipulation and operator unpredictability. We have developed a platform, reprogramming, expansion, and differentiation on Microcarriers, to solve these challenges.Materials and MethodsFive sources of human somatic cells were reprogrammed, selected, expanded and differentiated in microcarriers suspension cultures.ResultsImprovement of transduction efficiencies up to 2 times was observed. Accelerated reprogramming in microcarrier cultures was 7 days faster than monolayer, providing between 30 and 50‐fold more clones to choose from fibroblasts, peripheral blood mononuclear cells, T cells and CD34+ stem cells. This was observed to be due to an earlier induction of genes (β‐catenin, E‐cadherin and EpCAM) on day 4 versus monolayer cultures which occurred on days 14 or later. Following that, faster induction and earlier stabilization of pluripotency genes occurred during the maturation phase of reprogramming. Integrated expansion without trypsinization and efficient differentiation, without embryoid bodies formation, to the three germ‐layers, cardiomyocytes and haematopoietic stem cells were further demonstrated.ConclusionsOur method can solve the inherent problems of conventional monolayer cultures. It is highly efficient, cell dissociation free, can be operated with lower labor, and allows testing of differentiation efficiency without trypsinization and generation of embryoid bodies. It is also amenable to automation for processing more samples in a small footprint, alleviating many challenges of manual monolayer selection.We have developed an allied protocol for reprogramming, selecting, expanding and differentiating human pluripotent stem cells on Microcarriers (designated as RepMC). This method allows faster reprogramming, selecting 30‐50‐fold more candidates for characterization and also allows us to find high quality candidates that differentiate to cardiomyocytes and blood lineages. Mechanistically, this method appears to accelerate the induction, maturation and stabilization phases of reprogramming. Our findings help simplify the process of deriving and expanding iPSCs for therapeutic applications, offering a robust and scalable suspension platform for large‐scale generation of clinical grade iPSCs. 相似文献
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Unique crystal-originated pit (COP) distribution, similar to a striation pattern, is well matched with the oxygen profile in experimental analysis. It shows the strong relationship between oxygen concentration and COP distribution. In this paper, we study the generation of void defects and the relationship between interstitial oxygen and vacancy using the kinetic lattice Monte Carlo (KLMC) method. The KLMC method has been applied extensively in various forms to the study of micro-defects in silicon wafers. It explained well the formation of void defects such as vacancy–oxygen complex and vacancy–vacancy complex. The formation of clusters is strongly affected by oxygen concentration, which showed the relationship between COP distribution and oxygen concentration. The unique COP distribution could be correctly explained with KLMC results, and this kind of meso-scale results has not yet been reported. 相似文献
47.
Suk Young Oh Chun Hua Wu Elena Popova Eun Joo Hahn Kee Yoeup Paek 《Journal of Plant Biology》2009,52(4):348-354
We tested desiccation and/or vitrification procedures to cryopreserve the adventitious roots of Panax ginseng, the source of commercially produced ginsenosides. When only desiccation was applied, the post-freeze survival of 3- to 4-mm
root tips was <14% regardless of the composition of the preculture medium or the explant origin. Callus formation was frequently
observed after cryopreservation. In contrast, 90% survival and 32.5% root formation efficiency were achieved after cryopreservation
when a vitrification protocol was followed. Adventitious root cultures in flasks and bioreactors were reestablished from root
tips cryopreserved by vitrification. A prolonged lag-phase and lower biomass production were recorded in post-freeze-regenerated
cultures compared with control roots that were subcultured four times in flasks. However, biomass accumulations did not differ
between control and regenerated roots at the end of the sixth subculturing period. After 40 days of culture in bioreactors,
a mean value of 12.5 g dw L−1 was recorded for post-freeze-regenerated cultures versus 9.1 g dw L−1 for the control roots. Production of triol and diol ginsenosides in our bioreactor cultures also was enhanced after cryopreservation,
by 41.0% and 89.8%, respectively. These results suggest that the vitrification method is successful for cryopreservation of
P. ginseng adventitious roots. 相似文献
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49.
To investigate the effect of human pyruvate carboxylase (hPC) on lactate formation in Chinese hamster ovary (CHO) cell lines,
FLAG-tagged hPC was introduced into a dihydrofolate-deficient CHO cell line (DG44). Three clones expressing high levels of
hPC, determined by Western blotting using an anti-FLAG monoclonal antibody, and a control cell line were established. Immunocytochemistry
revealed that a substantial amount of expressed hPC protein was localized in the mitochondria of the cells. hPC expression
did not impair cell proliferation. Rather, it improved cell viability at the end of adherent batch cultures with the serum-containing
medium probably because of reduced lactate formation. Compared with control cells, specific lactate production rate of the
three clones was decreased by 21–39%, which was because of a decreased specific glucose uptake rate and yield of lactate from
glucose. Reduced lactate formation by hPC expression was also observed in suspension fed-batch cultures using a serum-free
medium. Taken together, these results demonstrate that through the expression of the hPC enzyme, lactate formation in CHO
cell culture can be efficiently reduced. 相似文献
50.