• Korean Journal of Microbiology
• /
• v.23 no.1
• /
• pp.64-68
• /
• 1985

In this study, hybridoma techniques were applied to produce monoclonal antobodies to Paragonimus westermani, commonly known as lung distoma. Balb/c mice were immunized intraperitoneally every week with increasing doses of purfied protein of Paragonimus westermani adult worms begining with 0.3/mg/mouse/7 days and ending with 0.5mg at 28th day. Spleen cells from these immunized mice were hybridized with myeloma cells (NS-1) and the hybridized cells were selected in HAT media. The antibody secreting cells among the hybrid cells were initially selected by ELISA. Those initially selected cells were further screened by the criteria of antibody producing activity, and seneral cell lines among them were further tested with immunodiffusion method. One hybridoma clone produced IgM and another clone produced IgG1. The supernatant of the hybridoma clone producing IgM had titer 1:64 and the hybridoma clone producing IgG1 had titer 1:256 measured by immunofluorescence technique.

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

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.8
• /
• pp.1102-1107
• /
• 2003

The ES cell can provide a useful system for studying differentiation and development in vitro and a powerful tool for producing transgenic animalds. To investigate the culture condition of chicken embryonic stem (CES) cells which can retain their multipotentiality or totipotency, three kinds of feeder layer cells, SNL cells, primary mice embryonic fibroblasts (PMEF) cells and primary chicken embryonic fibroblasts (PCEF) cells, were used as the feeder cells in media of DMEM supplemented with leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and stem cell factor (SCF) for co-culture with blastoderm cells from stage X embryos of chicken. The alkaline phosphatase (AKP) test, differentiation experiment in vitro and chimeric chicken production were carried out. The results showed that culture on feeder layer of PMEF yielded high quality CES cell colonies. The typical CES cells clone shape revealed as follows: nested aggregation (clone) with clear edge and round surface as well as close arrangement within the clone. Strong alkaline phosphatase (AKP) reactive cells were observed in the fourth passage cells. On the other hand, the fourth passage CES cells could differentiate into various cells in the absence of feeder layer cells and LIF in vitro. The third and fourth passage cells were injected into the subgerminal cavity of recipient embryos at stage X. Of 269 Hailan embryos injected with CES cells of Shouguang Chickens, 8.2% (22/269) survived to hatching, 5 feather chimeras had been produced. This suggests that an effective culture system established in this study can promote the growth of CES cells and maintain them in the state of undifferentiated and development, which lays a solid foundation for the application of CES cells and may provide an alternative tool for genetic modification of chickens.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.12
• /
• pp.7489-7496
• /
• 2013

This study was conducted to investigate enhancement of anti-tumor effects of the lentogenic Newcastle disease virus Clone30 strain (NDV rClone30) expressing cytosine deaminase (CD) gene against tumor cells and in murine groin tumor-bearing models. Cytotoxic effects of the rClone30-CD/5-FC on the HepG2 cell line were examined by an MTT method. Anti-tumor activity of rClone30-CD/5-FC was examined in H22 tumor-bearing mice. Compared to the rClone30-CD virus treatment alone, NDV rClone30-CD/5-FC at 0.1 and 1 MOIs exerted significant cytotoxic effects (P<0.05) on HepG2 cells. For treatment of H22 tumor-bearing mice, recombinant NDV was injected together with 5-FC given by either intra-tumor injection or tail vein injection. When 5-FC was administered by intra-tumor injection, survival for the rClone30-CD/5-FC-treated mice was 4/6 for 80 days period vs 1/6, 0/6 and 0/6 for the mice treated with rClone30-CD, 5-FC and saline alone, respectively. When 5-FC was given by tail vein injection, survival for the rClone30-CD/5-FC-treated mice was 3/6 vs 2/6, 0/6 and 0/6 for the mice treated with rClone30-CD, 5-FC or saline alone, respectively. In this study, NDV was used for the first time to deliver the suicide gene for cancer therapy. Incorporation of the CD gene in the lentogenic NDV genome together with 5-FC significantly enhances cell death of HepG2 tumor cells in vitro, decreases tumor volume and increases survival of H22 tumor-bearing mice in vivo.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.6
• /
• pp.771-776
• /
• 2001

A pregnant-induced clone was identified by differential screening from a cDNA library of bovine mammary gland. The clone was identified as a cDNA encoding a polyadenylate binding protein 1 (PABP). The cDNA clone had a total length of 1,911 nucleotides coding for 636 amino acids. The nucleotide sequence of the bovine PABP was 95% and 94% identical to those of human and mouse species, respectively. Comparison of the deduced amino acid sequences of bovine PABP with those of human species showed 100% identity. Induction of the PABP mRNA was observed in bovine mammary tissues at pregnant 7 and 8 months compared to virgin, lactating and involuted states. Expression of the PABP gene was examined in mammary epithelial HC11 cells at proliferating, differentiated and apoptotic conditions. The mRNA levels of PABP gene were similar between proliferating and differentiated cells, but expression levels were very low in apoptotic cells compared to other conditions. Results demonstrate that the PABP gene is induced during pregnancy at which stage mammary epithelial cells are actively proliferating.

• Korean Journal of Microbiology
• /
• v.50 no.2
• /
• pp.169-172
• /
• 2014

Recently, Hepatitis C virus (HCV) replication system has been established using human hepatoma cells (huh cell) and a variety of HCV clones. In this study, we established an infectious HCV replication system using huh7.5 cells and J6/JFH1 clone (genotype 2a). In addition, we investigated the antigen presentation capability of HCV-infected huh7.5 cells to HCV-specific T cells. Interestingly, HCV-infected huh7.5 cells were not capable of activating HCV-specific T cells. However, huh7.5 cells stimulated by exogenous HCV peptide were able to activate HCV-specific T cells, which was shown to produce TNF-${\alpha}$ and IFN-${\gamma}$. We further examined if HCV infection has an inhibitory effect on the expression of MHC class I molecule of huh7.5 cells. We found that HCV infection did not change the expression level of MHC class I molecule on huh7.5 cells.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.8
• /
• pp.3695-3700
• /
• 2012

Mammalian mediator (MED) is a multi-protein coactivator that has been identified by several research goups. The involvement of the MED complex subunit 19 (MED 19) in the metastasis of lung adenocarcinoma cell line (H1299), which expresses the MED 19 subunit, was here investigated. When MED 19 expression was decreased by RNA interference H1299 cells demonstrated reduced clone formation, arrest in the S phase of the cell cycle, and lowered metastatic capacity. Thus, MED 19 appears to play important roles in the biological behavior of non-small cell lung carcinoma cells. These findings may be important for the development of novel lung carcinoma treatments.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.5
• /
• pp.712-720
• /
• 2007

To investigate clonal variations of recombinant Chinese hamster ovary(rCHO) clones in response to culture pH and temperature, serum-free suspension cultures of two antibody-producing CHO clones(clones A and B), which were isolated from the same parental clone by the limiting dilution method, were performed in a bioreactor at pH values in the range of 6.8-7.6, and two different temperatures, $33^{\circ}C\;and\;37^{\circ}C$. In regard to cell growth, clone A and clone B displayed similar responses to temperature, although their degree of response differed. In contrast, clones A and B displayed different responses to temperature in regard to antibody production. In the case of clone A, no significant increase in maximum antibody concentration was achieved by lowering the culture temperature. The maximum antibody concentration obtained at $33^{\circ}C$(pH 7.4) and $37^{\circ}C$(pH 7.0) were $82.0{\pm}2.6$ and $73.2{\pm}4.1{\mu}g/ml$, respectively. On the other hand, in the case of clone B, an approximately 2.5-fold increase in maximum antibody concentration was achieved by lowering the culture temperature. The enhanced maximum antibody concentration of clone B at $33^{\circ}C$($132.6{\pm}14.9{\mu}g/ml$ at pH 7.2) was due to not only enhanced specific antibody productivity but also to prolonged culture longevity. At $33^{\circ}C$, the culture longevity of clone A also improved, but not as much as that of clone B. Taken together, CHO clones derived from the same parental clone displayed quite different responses to culture temperature and pH with regards antibody production, suggesting that environmental parameters such as temperature and pH should be optimized for each CHO clone.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.8
• /
• pp.4823-4827
• /
• 2013

Objective: To study the mechanism of effects of AZD1480 on the SKOV3 ovarian cancer cell line. Methods: The MTT method was used to assess cellular proliferation, flow cytometry for cellular apoptosis, the scratch test to determine migration, transwell chamber assays to detect cellular invasion, plate clone experiments to detect the clone forming ability and Western blotting to determine p-STAT3 protein levels. Results: The proliferation rate, migration ability, invasiveness and the clone forming ability of SKOV3 cells were reduced after treatment with AZD1480, while apoptosis rate and chemotherapeutic susceptibility were increased. After treatment with AZD1480 plus cisplatin, the apoptosis rate increased significantly while the expression level of p-STAT3 protein was decreased. Conclusion: AZD1480 can inhibit the proliferation, invasion, metastasis and clone formation of SKOV3 cells, induce cellulsar apoptosis, increase the chemotherapeutic sensitivity and reduce the expression level of p-STAT3 protein.

• IMMUNE NETWORK
• /
• v.13 no.2
• /
• pp.63-69
• /
• 2013

IL-12 is a secretory heterodimeric cytokine composed of p35 and p40 subunits. IL-12 p35 and p40 subunits are sometimes produced as monomers or homodimers. IL-12 is also produced as a membrane-bound form in some cases. In this study, we hypothesized that the membrane-bound form of IL-12 subunits may function as a costimulatory signal for selective activation of TAA-specific CTL through direct priming without involving antigen presenting cells and helper T cells. MethA fibrosarcoma cells were transfected with expression vectors of membrane-bound form of IL-12p35 (mbIL-12p35) or IL-12p40 subunit (mbIL-12p40) and were selected under G418-containing medium. The tumor cell clones were analyzed for the expression of mbIL-12p35 or p40 subunit and for their stimulatory effects on macrophages. The responsible T-cell subpopulation for antitumor activity of mbIL-12p35 expressing tumor clone was also analyzed in T cell subset-depleted mice. Expression of transfected membranebound form of IL-12 subunits was stable during more than 3 months of in vitro culture, and the chimeric molecules were not released into culture supernatants. Neither the mbIL-12p35-expressing tumor clones nor mbIL-12p40-expressing tumor clones activated macrophages to secrete TNF-${\alpha}$. Growth of mbIL-12p35-expressing tumor clones was more accelerated in the $CD8^+$ T cell-depleted mice than in $CD4^+$ T cell-depleted or normal mice. These results suggest that $CD8^+$ T cells could be responsible for the rejection of mbIL-12p35-expressing tumor clone, which may bypass activation of antigen presenting cells and $CD4^+$ helper T cells.