• KSBB Journal
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• 제27권3호
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• pp.186-194
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• 2012

Various human host cell lines, which are more effective than the other original human cell lines, have been developed and used. Highly efficient human cell line can be obtained from the fusion between human embryonic kidney 293 (HEK293) and human Burkitt's lymphoma cells (Namalwa). Fused cell line has the advantages of both cell lines such as the high transfection efficacy of HEK293 cells and the constitutive expression of Epstein-Barr virus (EBV) genome which is related with high expression of target protein and anti-apoptotic growth of Namalwa cells. In this study, characterization of two original cell lines was performed by using design of experiment (DOE) considering cell maintenance, media development, optimization of culture condition, and scale-up. The formation of aggregates was apparent with high glutamine concentration at more than 6 mM. Supplementation of hydrolysates showed positive effects on the growth performances of HEK293 cells. On the contrary, Namalwa cells showed negative results. It was confirmed that Namalwa cells were more sensitive to lower temperature at $35^{\circ}C$ and hyperosmotic condition over 260 mOsm/kg. In addition, both cell lines showed limited growth in 3-L bioreactor due to shear stress.

• The Korean Journal of Physiology
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• 제29권2호
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• pp.301-307
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• 1995

To explore electrophysiological properties of the ${\delta}-Opioid$ receptors artificially expressed in the mammalian cell, effect of an opioid agonist DPDPE $(1\;{\mu}M)$ on the voltage-sensitive outward currents was examined in the HEK293 (human embryonic kidney) cells transfected with ${\delta}-Opioid$ receptor cDNA cloned from NG-108-15 $(neuroblastoma\;{\times}\;glioma\;hybrid)$ cDNA library. Also studied were effects of 8-bromo-cyclic AMP and naloxone on DPDPE-induced changes in the voltage sensitive outward current. The voltage sensitive outward currents were recorded using perforated patch technique at room temperature. In the non-transformed HEK293 cells, DPDPE did not alter voltage sensitive outward current, indicating that no native ${\delta}-Opioid$ receptor had been developed. However, $(1\;{\mu}M)$ DPDPE remarkably increased the voltage sensitive outward current in the transformed HEK293 cells. The increment in voltage sensitive outward current peaked in $7{\sim}10\;minutes$ after DPDPE application, and the maximum DPDPE-activated outward current $(313.1{\pm}12.3\;pA)$ was recorded when the membrane potential was depolarized to +70mv. Following pretreatment of the transformed HEK293 cells with 1 mM 8-bromo-cyclic AMP, DPDPE failed to increase the voltage sensitive outward currents. On the other hand, naloxone completely abolished DPDPE-activated voltage sensitive outward current in the transformed HEK293 cells. The results of present study suggest that in the transformed HEK293 cells an activation of the ${\delta}-Opioid$ receptors by an opioid agonist DPDPE increases the voltage-sensitive potassium current as a result of decrement in cyclic AMP level.

• Animal cells and systems
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• 제14권2호
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• pp.83-89
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• 2010

Gangliosides are a ubiquitous component of the membranes of mammalian cells that have been suggested to play important roles in various cell functions such as cell-cell interaction, adhesion, cell differentiation, growth control and signaling. However, the role that gangliosides play in the immune rejection response in xenotransplantation is not yet clearly understood. In this study, differential expression patterns of gangliosides in HEK293 (human embryonic kidney cells), PK15 (porcine kidney cells), NIH-kd (NIH-mini pig kidney cells, primary cultured) and the cortex, medulla and calyx of the NIH-mini pig kidney were investigated by high-performance thin-layer chromatography (HPTLC). The results revealed that HEK293, PK15 and NIH-kd contained GM3, GM2 and GD3 as major gangliosides. Moreover, GM3, which are the gangliosides of NIH-kd, were expressed at higher levels than HEK293 and PK15. Especially, GT1b were expressed in HEK293 and NIH-kd but not in PK15. Finally, GM1 and GD1a were expressed in NIH-kd, but not in HEK293 or PK15. These results suggest that differential expression patterns of gangliosides from HEK293, PK15 and NIH-kd are related to the immune rejection response in xenotransplantation.

• 대한한의학회지
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• 제40권2호
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• pp.94-105
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• 2019

Objectives: The correlation between medicinal herbal formulas and a risk of cardiotoxicity has been controversial. Thus, this study investigated cardiac safety assessment of 52 most commonly used medicinal herbal formulas. Methods: We evaluated the in vitro effects of medicinal herbal formulas on recombinant human embryonic kidney 293 (HEK 293) cell line expressing human ether-a-go-go-related gene (hERG) potassium channel. Results and Conclusion: Our results demonstrated that all of 52 medicinal herbal formulas did not show inhibition of hERG current in hERG-HEK 293 recombinant cells. In conclusion, these safety data suggest that 52 medicinal herbal formulas were not associated with an increased risk of cardiotoxicity in hERG-HEK 293 recombinant cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9885-9889
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• 2014

Background: Tumor necrosis factor (TNF) related apoptosis-inducing ligand (TRAIL) is an antitumor candidate in cancer therapy. This study focused on effects of TRAIL, as a proapototic ligand that causes apoptosis, in B-CELL chronic lymphocytic leukemia cells (B-CLL). Materials and Methods: A population of HEK 293 cells was transducted by lentivirus that these achieved ability for producing the TRAIL protein and then HEK 293 cells transducted were placed in the vicinity of CLL cells. After 24 hours of co-culture, apoptosis of CLL cells was assessed by annexin V staining. Results: The amount of Apoptosis was examined separately in four groups: 293 HEK TRAIL ($16.17{\pm}1.04%$); 293 HEK GFP ($2.7{\pm}0.57%$); WT 293 HEK ($2{\pm}2.6%$); and CLL cells ($0.01{\pm}0.01%$). Among the groups studied, the maximum amount of apoptosis was in the group that the vector encoding TRAIL was transducted. In this group, the mean level of soluble TRAIL in the culture medium was 253pg/ml; also flow cytometry analyzes showed that proapotosis in this group was $32.8{\pm}1.6%$, which was higher than the other groups. Conclusions: In this study, we have demonstrated that TNF secreted from HEK 293 cells are effective in death of CLL cells.

• The Korean Journal of Physiology and Pharmacology
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• 제9권1호
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• pp.63-68
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• 2005

Hydrogen peroxide ($H_2O_2$) causes oxidative stress and is considered as an inducer of cell death in various tissues. Two-pore domain $K^+$ ($K_{2p}$) channels may mediate $K^+$ efflux during apoptotic volume decreases (AVD) in zygotes and in mouse embryos. In the present study, we sought to elucidate linkage between $K_{2p}$ channels and cell death by $H_2O_2$. Thus $K_{2p}$ channels (TASK-1, TASK-3, TREK-1, TREK-2) were stably transfected in HEK-293 cells, and cytotoxicity assay was preformed using cell counting kit-8 (CCK-8). Cell survival rates were calculated using the cytotoxicity assay data and dose-response curve was fitted to the $H_2O_2$ concentration. Ionic currents were recorded in cell-attached mode. The bath solution was the normal Ringer solution and the pipette solution was high $K^+$ solution. In HEK-293 cells expressing TREK-1, TREK-2, TASK-3, $H_2O_2$ induced cell death did not change in comparison to non-transfected HEK-293. In HEK-293 cells expressing TASK-1, however, dose-response curve was significantly shifted to the left. It means that $H_2O_2$ induced cell death was increased. In cell attached-mode recording, application of $H_2O_2$ (300μM) increased activity of all $K_{2p}$ channels. However, a low concentration of $H_2O_2$ ($50{\mu}M$) increased only TASK-1 channel activity. These results indicate that TASK-1 might participate in $K^+$ efflux by $H_2O_2$ at low concentration, thereby inducing AVD.

• Molecules and Cells
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• 제37권9호
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• pp.691-698
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• 2014

SCYL1-BP1 is thought to function in the p53 pathway through Mdm2 and hPirh2, and mutations in SCYL1-BP1 are associated with premature aging syndromes such as Geroderma Osteodysplasticum; however, these mechanisms are unclear. Here, we report significant alterations in miRNA expression levels when SCYL1-BP1 expression was inhibited by RNA interference in HEK293T cells. We functionally characterized the effects of potential kernel miRNA-target genes by miRNA-target network and protein-protein interaction network analysis. Importantly, we showed the diminished SCYL1-BP1 dramatically reduced the expression levels of EEA1, BMPR2 and BRCA2 in HEK293T cells. Thus, we infer that SCYL1-BP1 plays a critical function in HEK293T cell development and directly regulates miRNA-target genes, including, but not limited to, EEA1, BMPR2, and BRCA2, suggesting a new strategy for investigating the molecular mechanism of SCYL1-BP1.

• Molecules and Cells
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• 제22권2호
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• pp.198-202
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• 2006

The $P2X_7$ receptor, an ATP-gated cation channel, induces cell death in immune cells and is involved in neurodegenerative diseases. Although the receptor plays various roles in these diseases, the cellular mechanisms involved are poorly understood and antagonists are limited. Here, the development of a cell-based assay for human $P2X_7$ receptor is reported. We established permanent lines of HEK 293 cells expressing a high level of $hP2X_7$ receptor. Functional activity of the $hP2X_7$ receptor was confirmed by whole-cell patch recording of ATP-induced ion currents. Prolonged exposure to ATP resulted in death of the $hP2X_7$-expressing HEK 293 cells and this cell death could be quantified. Two known $P2X_7$ antagonists, PPADS and KN-62, blocked ATP-induced death in a concentration-dependent manner. Thus, this assay can be used to screen for new antagonists of $hP2X_7$ receptors.

• Journal of Ginseng Research
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• 제37권2호
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• pp.201-209
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• 2013

Ginsenoside, one of the active ingredients of Panax ginseng, has a variety of physiologic and pharmacologic effects. The purpose of this study was to explore the effects of ginsenoside Rd (G-Rd) on melastatin type transient receptor potential 7 (TRPM7) channels with respect to the proliferation and survival of AGS and MCF-7 cells (a gastric and a breast cancer cell line, respectively). AGS and MCF-7 cells were treated with different concentrations of G-Rd, and caspase-3 activities, mitochondrial depolarizations, and sub-G1 fractions were analyzed to determine if cell death occurred by apoptosis. In addition, human embryonic kidney (HEK) 293 cells overexpressing TRPM7 channels were used to confirm the role of TRPM7 channels. G-Rd inhibited the proliferation and survival of AGS and MCF-7 cells and enhanced caspase-3 activity, mitochondrial depolarization, and sub-G1 populations. In addition, G-Rd inhibited TRPM7-like currents in AGS and MCF-7 cells and in TRPM7 channel overexpressing HEK 293 cells, as determined by whole cell voltage-clamp recordings. Furthermore, TRPM7 overexpression in HEK 293 cells promoted G-Rd induced cell death. These findings suggest that G-Rd inhibits the proliferation and survival of gastric and breast cancer cells by inhibiting TRPM7 channel activity.

• Journal of Yeungnam Medical Science
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• 제20권2호
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• pp.142-151
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• 2003

To induce bone formation at ectopic site by tissue engineering and gene therapy, we transplanted collagen sponges containing rhBMP-7 transduced HEK 293 cells in the hypodermis of nude mice. Bone formation was investigated by histological and electron microscopic method at 3, 6, and 9 weeks after transplantation. At 9 weeks after transplantation, eosinophilic bony tissue was observed in the implanted collagen sponge and was confirmed as bone tissue by Von Kossa stain. In the transmission electron microscopic observation, the cells in newly formed bone tissue had eccentrically located nucleus and well developed rough endoplasmic reticulum (rER). Therefore, the cells were evaluated as osteoblasts. Those results suggest that it is possible to form a bone tissue in the ectopic site by transplantation of rhBMP-7 transduced HEK 293 cells. This will be contributed to push more advanced gene therapy for bone formation. However, the HEK 293 cell is unable to apply to the clinical gene therapy. Therefore it is worth to find more compatible cells for clinical application. In addition, collagen sponge is considered as an excellent scaffold and/or carrier for gene therapy and a good biomaterial for tissue engineering.