• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.197-201
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• 2003

The recombinant plasmids harboring a heterologous gene coding mouse endostatin were transfected and expressed stably in Trichoplusia ni Tn 5B1-4 cells and Bombyx mori BmN cells, respectively. Recombinant endostatin expressed in the stably transformed Tn 5B1-4 and BmN cells was secreted into the medium. BmN cells are relatively lower in maximum cell growth and recombinant endostatin production than Tn 5B 1-4 cells. Recombinant endostatin was also purified to homogeneity using a simple one-step ${Ni^2+}$ affinity fractionation method. Purified recombinant endostatin inhibited endothelial cell proliferation in a dose-dependent manner. The concentration at half-maximum inhibition $({ED_50})$ for recombinant endostatin was approximately 0.35 ${\mu}g$/ml.

• KSBB Journal
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• v.13 no.2
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• pp.181-186
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• 1998

In order to obtain high-level production of recombinant human thrombopoietin (rhTPO) in insect cell line, HTI-TN-5B1-4 (TN5), conditions for optimal rhTPO expression such as multiplicity of infection (MOI), the cell density at infection, harvesting time and type of culture method as well as growth media were determined. When TN5 cells were cultured as anchorage-dependent state in 60-mm dish, cell density $2\times^6$ cells,MOI of 10 and Garvesting the culture media at 72 hr post-infection wrere the cinditions for highest rh TPO production. High production of rhTPO was also achieved by using EXPRESS FIVE serum free media rather than SF900II serum free media-1. Anchorage-dependent TN5 cells were adapted as a suspension culture when they were grown in the presence of heparin. TN5 cells were successfully cultured at 0.2 L scale in suspension culture without having aggregation. When TN5 cells were cultured as suspension state, cell density of $0.6\times10^6$ cells/mL, MOI of 1 and harvesting the culture media at 72 hr post-infection, gave the highest yield of rhTPO.

• BMB Reports
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• v.31 no.5
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• pp.453-458
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• 1998

Human thrombopoietin (hTPO) was expressed to high levels in insect cells using the baculovirus expression system. Full-length hTPO cDNA containing a native signal peptide sequence was amplified by PCR from a human fetal liver cDNA library and cloned into the Autographa californica nuclear polyhedrosis virus (AcNPV) expression vector. Immunoblot analysis with antiserum against hTPO indicated that an approximately 55 kDa protein was produced in recombinant AcNPV infected insect cells. Recombinant hTPO was produced 4-fold higher in Trichoplusia ni (Tn5) cells than in Spodoptera frugiperda (Sf9) cells. with most of the hTPO produced in Tn5 cells secreted into the culture medium. Addition of tunicamycin in the culture medium resulted in the reduction of the size of hTPO to 35-38 kDa, and most of the protein remained within the cell. These results suggest that N-glycosylation of hTPO is required for the secretion of the protein into the culture medium in insect cells. hTPO produced in insect cells induced proliferation and maturation of megakaryocyte progenitors, indicating that it is in a biologically active form.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.4
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• pp.239-252
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• 2007

Objectives: In the present study, we examined the differentiation potential of human adipose-(HAD) and human umbilical cord-derived mesenchymal like stem cells (HUC) into cardiomyocytes. Methods: Cells were initially exposed to 5-azacytidine for 24h cells and then were cultivated in the presence or absence of activin A, TGF-$\beta$1, or Wnt inhibitor with various combinations of BMP and FGF. Assessment of cardiomyogenic differentiation was made upon the expression of cardiomyocyte-specific genes using RT-PCR. Results: HAD that cultivated in control medium for 4 weeks after 5-azacytidine expose showed new expression of TnT gene and increased expression of Cmlc1 and kv4.3 genes. However, HAD cultivated in the presence of combinations of BMP-4/FGF-4 (B4/F4) and BMP-4/FGF-8 (B4/F8) showed new expression of $\beta$-MHC gene and more increased expression of Cmlc1, TnT, TnI, Kv4.3 genes. Significantly enhanced expression of Cmlc1, TnT, and Kv4.3 genes were also observed compared to that cultivated in the control medium. Treatment of HUC with either 5-azacytidine or combinations of BMP and FGF did not affect the expression profile of these genes. However, when activin A or TGF-$\beta$1 was present in addition to the BMP-2/FGF-8 (B2/F8) after 5-azacytidine exposure, HUC exhibited new expression of $\beta$-MHC gene and increased expression of $\alpha$-CA, TnT and Kv4.3 genes. When Wnt inhibitor was present in addition to BMP and FGF, HUC showed new expression of Cmlc1 gene and increased expression of $\alpha$-CA, TnT, TnI and Kv4.3 genes. Conclusions: Based on these observations, it is suggested that HAD and HUC could differentiate into cardiomyocytes which might be used as therapeutic cells for the heart diseases.

• Korean Journal of Microbiology
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• v.27 no.4
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• pp.323-333
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• 1989

Plasmid DNA molecules containing strong promoter upstream from IS50L or IS50R, the two insertion sequences that flank Tn5, were constructed to amplify the synthesis of Tn5-encoded polypeptides. When proteins made by cells that contain these plasmids were analyzed on polyacrylamide gels, enhanced synthesis of IS50R polypeptides could be detected. Synthesis of this polypeptide apparently is initiated within the large open reading frame of this element. In addition, the stability of IS50L-and IS50R-encoded polypeptides was analyzed. It was found that IS50L polypeptides are relatively unstable in vivo. This instability could account for the observed inability of this element to promote transposition.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.39-46
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• 1994

Pseudomonas fluorescens Biovar III strains S-2 antagonistic to Rhizoctonia solani was subjected to Tn5 mutagenesis by the transposon vector pGS9. Ampicillin and kanamycin resistant (Ampr, Kmr) transconjugants were recovered at a frequency of 1.3$\times$10-7 per initial recipient cell, when recipient cells were washed twice in TE buffer before conjugation. Of the ca. 3000 transconjugants, a frequency of noninhibitory (Inh-), nonfluorescent (Flu-) and auxotorphic (Pro-) mutants were 0.27%, 0.47% and 0.40%, respectively. In these mutants, all Inh- mutants showed the same colony morphology as wild type, whereas all Flu- and Pro- mutants inhibited the growth of R. solani. These mutants were also susceptible to chloramphenicol, indicating only the Tn5 element, except for parts of pGS9, was integrated into the recipient genome. In a Southern blot analysis, the Tn5 element inserted into one site on the chromosome for each of the chosen mutants. However, Tn5 insertion sites of Inh-, and Pro- mutants were differed in each other. These indicate that the genes essential for R. solani inhibition, fluorescent production and auxotrophic are chromosomally located, but not linked to each other.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.338-338
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• 2009

To date, rubbing has been widely used to align LC molecules uniformly. Although rubbing can be simple, it has fundamental problems such as the generation of defects by dust and static electricity, and difficulty in achieving a uniform LC alignment on a large substrate. Therefore, noncontact alignment has been investigated. Ion beam induced alignment method, which provides controllability, nonstop process, and high resolution display. We investigated the high pretilt angle effects on electro-optical properties of ion beam (IB)-irradiated liquid crystal cells. on a blended polymer surface. High pretilt angle of liquid crystals IB-irradiated on a blended polymer surface including such as 5% and 10% of homeotropic polymer contents can' be achieved. The threshold voltages of IB-irradiated twisted nematic (TN) cells on a blended polymer surface decrease with increasing the pretilt angle. Also, the rising time of IB-irradiated TN cells decreases with increasing the pretilt angle. However the decay time of IB-irradiated TN cells increases with increasing the pretilt angle. Consequently, the electro-optical properties of IB-irradiated TN cells depend strongly on the pretilt angle in a blended polymer surface.

• Korean Journal of Optics and Photonics
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• v.21 no.2
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• pp.69-73
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• 2010

We propose a method to enhance the response time of a twisted nematic liquid crystal (TN-LC) cell using an anisotropic polymer. Polymer networks are formed by the phase separation between a LC and a UV-curable polymer. A TN-LC cell is exposed to UV light after the mixture of LC and anisotropic polymer is injected into the TN-LC cell. As a result, turn-off time of a TN-LC cell can be decreased remarkably without any loss of the transmittance. The turn-off time of a TN-LC cell with pure LC was 16 ms, but those of polymer networked TN-LC cells were 12, 11, and 9 ms when the concentration of the polymer was 3, 5, and 10 wt%, respectively. Moreover, by virtue of the polymer network, the backflow effect and the delay time generated during the turn-off process disappeared.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.289-290
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• 2005

We have investigated the electro-optical (EO) performances of the flexible liquid crystal display (LCD) on twisted nematic (TN) mode according to variation of cell gap in comparison with glass LCD. There were four kinds of cells which were having cell gaps of 3$\mu$m, 4$\mu$m and 5$\mu$m, especially the lowest 2$\mu$m on flexible and glass substrates separately. The EO performances of the flexible cells on the rubbed potyimide (PI) were almost the same those of glass cells. The response time of flexible cells was shorter than that of glass cells but the alignment of liquid crystal (LC) of flexible cells was weaker than that of glass cells. The residual DC of flexible cells was on the increase like that of glass cells in compliance with lowering cell gap.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.173-181
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• 2004

To delay the onset of apoptosis in the culture, transformed Tn 5B1-4 cells harboring anti-apoptotic genes, bcl-2 and baculovirus p35, have been established and analyzed for their anti-apoptotic ability in suspension culture using spinner flasks. In the suspension culture at agitation speeds of 100 rpm and 200 rpm, the cell growth of cell clone expressing Bcl-2 protein was much higher than other two clones and the maximum cell density of the clone was 6.0 ${\times}$ 10$^{6}$ cells/ml and 6.2 ${\times}$ 10$^{6}$ cells/ml at day three of the incubation. On the other hand, the cell growth of cell clone expressing baculovirus protein P35 was much higher than other two clones in suspension culture at agitation speed of 300 rpm and the maximum cell density of the clone was 6.1 ${\times}$ 10$^{6}$ cells/ml at day three of the incubation. Based on the pattern of genomic DNA laddering and the microscopic observation of apoptotic bodies, the more apoptotic bodies are induced in Tn 5B1-4 control cell clone at higher agitation speed. This result shows that the shear stress can be a main factor in inducing apoptosis in spinner flask culture. At low agitation speed, cell clone expressing Bcl-2 was more effective in delaying the onset of apoptosis than the cell clone expressing P35. On the other hand, at high agitation speed, cell clones expressing baculovirus P35 was more effective in delaying the onset of apoptosis than the cell clone expressing Bcl-2. Therefore, anti-apoptotic genes, bcl-2 and baculovirus p35, can playa distinct role depending on agitation speed in the suspension culture.