• Journal of Microbiology
• /
• v.45 no.6
• /
• pp.572-577
• /
• 2007

To enhance therapeutic potential of murine monoclonal antibody, humanization by CDR grafting is usually used to reduce immunogenic mouse residues. Most humanized antibodies still have mouse residues critical for antigen binding, but the mouse residues may evoke immune responses in humans. Previously, we constructed a new humanized version (AKA) of mouse CC49 antibody specific for tumor-associated glycoprotein, TAG-72. In this study, to select a completely human antibody light chain against TAG-72, guided selection strategy using phage display was used. The heavy chain variable region (VH) of AKA was used to guide the selection of a human TAG-72-specific light chain variable region (VL) from a human VL repertoire constructed from human PBL. Most of the selected VLs were identified to be originated from the members of the human germline VK1 family, whereas the VL of AKA is more homologous to the VK4 family. Competition binding assay of the selected Fabs with mouse CC49 suggested that the epitopes of the Fabs overlap with that of CC49. In addition, they showed better antigen-binding affinity compared to parental AKA. The selected human VLs may be used to guide the selection of human VHs to get completely human anti-TAG72 antibody.

• Biomedical Science Letters
• /
• v.14 no.3
• /
• pp.167-172
• /
• 2008

We compared the clinical efficacy of LED therapy using 880 nm and 630 nm LED to test collagen accumulations in subcutaneous tissue of mouse after LED irradiation by measuring the quantity of collagen. 880 nm and 630 nm LED was irradiated on the back of ICR mouse given at $10.8J/cm^2$ followed for 30 minutes everyday for 5 weeks. Histological observation was performed by Hematoxylin & Eosin staining and Masson's Trichrome collagen staining. We also used Sircol soluble collagen assay kit for measuring the amounts of collagen in the mouse skin tissue after 1, 3, and 5 weeks post LED irradiation, respectively. Collagen generation was found at subcutaneous tissue, and the quantity of collagen in 880 nm LED group had grown more than that of 630 nm LED group at 5 weeks follow-up later. About 75% more efficacies for collagen generation were found in the group of 5th week of 880nm LED irradiation. The efficacy of 880nm LED could be more useful than 630 nm LED for synthesizing collagens in mouse subcutaneous tissue as time followed.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.4
• /
• pp.462-466
• /
• 2001

To understand molecular mechanisms of mouse mammary gland involution, clones were isolated by differential screening of a cDNA library. Partial sequences of a clone showed 100% identity to cDNA sequences of mouse lysozyme P gene. Northern analysis was performed to examine expression levels of lysozyme mRNA in mammary gland at several physiological states. Expression of lysozyme gene was induced at involution day 5 compared with lactating stage. High levels of lysozyme mRNA were also detected at virgin tissues. Two types of separate genes, P and M lysozyme, have been known in mouse, and we found that both lysozyme P and M genes were expressed in mammary tissues by reverse transcriptase-polymerase chain reaction. The lysozyme enzyme activity determined by lysoplate assay was also higher in involuted mammary tissues compared with lactating tissues, showing a similar trend to its mRNA levels. Lysozyme is an antimicrobial protein and involved in host defense mechanism. The increase in lysozyme gene expression may help to prevent microbial infection during mammary gland involution at which stage the residual milk in the mammary gland provides good nutritional sources for microbial growth.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.17 no.4
• /
• pp.1008-1012
• /
• 2003

In order to evaluate the cytotoxic effect of reactive oxygen species(AOS), the cell viability was measured by MTT assay after cultured mouse hippocampal neurons were treated with various concentrations of xanthine oxidase(XO) and hypoxanthine (HX) for 5 hours. And also, the protective effect of Salviae Mutiorrhizae Radix(SMR) on XO/HX-induced neurotoxicity was examined in these cultures. XO/HX significantly decreased cell viability in dose-and time dependent manners when cultured mouse hippocampal neurons were treated with 5～40 mU/ml XO for 5 hours. In the protective effect of SMA, SMR increased cell viability dose-dependently after cultured mouse hippocampal neurons were preincubated with 30～120 ㎍/ml SMR for 2 hours. From these results, it is suggested that XO/HX is toxic on cultured mouse hippocampal neurons, and herbe medicine such as SMR is very effective in blocking the cytotoxicity induced by AOS.

• Korean journal of food and cookery science
• /
• v.17 no.6
• /
• pp.617-624
• /
• 2001

Gamma irradiation (1-10 kGy) was applied to chicken for the evaluation of their microbiological safety and possible genotoxicity. In 3 kGy-irradiated sample, the growth of psychrophile was inhibited about 1.5 log cycles and no cells were recovered in total microbial counts. All kinds of contaminated microorganism were sterilized by 7 kGy-irradiation. Also, irradiation followed by freeze-storage at the same time was very effective in inhibiting bacterial growth. The genotoxicity of 10 kGy-irradiated chicken was evaluated by Salmonella Typhimurium reversion assay and in vivo micronucleus assay using mouse bone marrow cells. The results were negative in the bacterial reversion assay with S. Typhimurium TA98, TA100, TA1535, and TA1539. Clastogenic effects were not shown in vivo mouse micronucleus assay at 10 kGy-dose tested.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.23 no.1
• /
• pp.95-104
• /
• 2007

I. Objective The primary requirement of an endodontic root canal sealer is the biologic compatibility, because they remain in close contact with living periapical tissues over a long period of time. The aim of this study was the evaluation of cytotoxicity and genotoxicity of resin-based root canal sealers, AH 26 and ADSEAL. II. Material & Methods In this study, human periodontal ligament cells, human oral cancer cells (KB) and mouse osteoblasts (MC-3T3-E1) were used. Specimens of AH26, ADSEAL were eluted with culture medium for 1, 3, 5 and 7 days. Cytotoxicity was evaluated by using tetrazolium bromide reduction assay (MTT assay) for mitochondrial enzyme activity and cell viability. Genotoxicity was evaluated by using alkaline single cell gel electrophoresis assay (Comet assay). Also cell apoptosis induced by AH 26 was detected by Hoechst33258 staining. III. Results AH 26 and ADSEAL exhibited cytotoxic effects in all investigated cell groups. Genotoxicity was also noted for both sealers in mouse osteoblasts (MC-3T3-E1). But, ADSEAL presented significantly low cytotoxicity and genotoxicity compared with AH 26. Cytotoxicity and genotoxicity induced by AH 26 resulted in apopotosis. IV. Conclusion Our results clearly indicate that the recently invented ADSEAL has better biocompatibility than another resin based root canal sealer, AH 26. However ideal root canal sealer should have not only biocompatibility but also satisfactory physico-chemical properties such as sealing ability and stability. Thus continuous studies and developments should follow.

• Toxicological Research
• /
• v.14 no.3
• /
• pp.453-457
• /
• 1998

In order to evaluate the mutagenic potential of Intralipidos produced by Greenmate cooperation. We performed Salmonella typhimurium reversion assay, chromosomal aberration test on chinese hamster ovarian cells and in vivo micronucleus assay using mouse bone marrow cells. In the reverse mutation test using Salmonella typhimurium TA98 and TA100, Intralipidos did not increase the number of revertant at any of the concentration tested in this study. Intralipidos did not increase the number of cells having structural or numberical chromosome aberration in cytogenetic test. In mouse micronucleus test, no significant increase were observed in the occurrence of micornucleated polychromatic erythrocytes in ICR male mice intraperitoneally administered with Intralipidos. These results indicate that Intralipidos has no genetic toxicity under these experimental conditions.

• Proceedings of the Korea Society of Environmental Toocicology Conference
• /
• 2003.05a
• /
• pp.185-185
• /
• 2003

To develope the novel anti-allergic drug, many sophoricoside derivatives were synthesized. Among these derivatives, JSH-II-3, JSH-Ⅵ-3, JSH-Ⅶ-3, and JSH-Ⅷ-3 were selected and subjected to high throughput toxicity screening (HTTS) because they revealed strong IL-5 inhibitory activity and limitation of quantity. Mouse lymphoma thymidine kinase (tk$\^$+/-/) gene assay (MOLY) and single cell gel electrophoresis (Comet) assay in mammalian cells were used as HTTS tool in our laboratory. In MOLY assay, JSH-Ⅶ-3 at 50 ∼ 6 $\mu\textrm{g}$/ml concentrations was not shown significant mutagenic effect in the absence and presence of S-9 metabolic activation system. However, the concentration of ISH-II-3, 38 $\mu\textrm{g}$/ml, induced increased mutation frequency (MF) in the presence of S-9 metabolic activation system. Also in comet assay, DNA damage was not observed in JSH-Ⅵ-3 and JSH-Ⅶ-3, wherase concentration of 32.8 $\mu\textrm{g}$/ml in JSH-II-3 and 13.9 $\mu\textrm{g}$/ml in JSH-Ⅶ-3 were induced DNA damage in the absence of S-9 metabolic activation system. Therefore, we suggest that JSH-Ⅵ-3 and JSH-Ⅶ-3 have no genotoxic effects but JSH-II-3 and JSH-Ⅷ-3 induce some mutagenicity and DNA strand breaks in mouse lymphoma cell line used this study.

• Journal of Nutrition and Health
• /
• v.36 no.3
• /
• pp.255-261
• /
• 2003

Food irradiation has been steadily increasing in many countries in line with increasing international trade and concerns about naturally occurring harmful contaminants in food. Although irradiation provides an excellent safeguard for the consumer by destroying almost 100% of harmful bacteria, it is necessary to ensure the safety of irradiated foods. This study was performed to investigate the effect of an irradiated diet on lipid peroxidation in the plasma, liver, small intestinal mucosa, and lymphocyte DNA damage in mice. Eight-week old ICR mice were assigned to two groups to receive either non-irradiated or irradiated (10 kGy) diets containing 20.38% fish powder and 6.06% sesame seeds for 4 weeks. The resulting changes in the degrees of lipid peroxidation were evaluated based on the level of plasma and liver thiobarbituric acid reactive substance (TBARS), transmission electron micrograph of jejunal mucosa, and free radical-induced oxidative DNA damage in lymphocytes, as measured by alkaline comet assay (single cell gel electrophoresis). The peroxide values of the gamma irradiated diet were measured every week, and the sample for comet assay was taken at the end of the four week experimental period. There was no significant difference in food efficiency ratio between the two groups. The peroxide values of the diet were immediately increased to 35.5% after gamma irradiation and kept on increasing during storage. After 4 weeks, no differences in tissue or plasma TBARS value were observed between the two groups, but epithelial cells of jejumum showed osmiophillic laminated membranous structures, considered as myelin figures,. The oxidative DNA damage expressed as tail moment (TM) increased 30% in the blood lymphocytes of the mice fed the irradiated diet. In conclusion, the comet assay sensitively detected differences in lymphocyte DNA damage after feeding with the irradiated diet for 4 weeks. However, in order to ensure the safety of irradiated foods, it would be more useful to conduct a long-term feeding regimen using an irradiated diet and examine the level of lipid peroxidation and the state of oxidative stress in a greater range of organs.

• Molecular & Cellular Toxicology
• /
• v.3 no.1
• /
• pp.53-59
• /
• 2007

This study was conducted to evaluate the mutagenic potential of dimethyl isophthalate (DMIP) using Ames bacterial reverse mutation test, chromosomal aberration test and mouse lymphoma $tk^{+/-}$ gene assay. As results, in Ames bacterial reversion assay, DMIP was tested up to the concentration of 5,000 ${\mu}g$/plate and did not induce mutagenicity in Salmonella typhimurium strains TA98, TA100, TA1535 and TA1537, and Escherichia coli WP2uvrA with or without metabolic activation (S9 mix). Using cytotoxicity test, the maximal doses of DMIP for chromosomal aberration assay were determined at 1,250 ${\mu}g/mL$, which was a minimum precipitation concentration ($IC_{50}>1,940\;{\mu}g/mL$ or 10 mM) and at 155 ${\mu}g/mL$ ($IC_{50}:155\;{\mu}g/mL$) in the presence and the absence, respectively, of S9 mix. DMIP in the presence of S9 mix induced statistically significant (P<0.001) increases in the number of cells with chromosome aberrations at the dose levels of over 250 ${\mu}g/mL$, when compared with the negative control. However, DMIP in the absence of S9 mix did not caused significant induction in chromosomal aberrant cells. In MLA, DMIP at the dose range of 242.5-1,940 ${\mu}g/mL$ in the presence of S9 mix induced statistically significant increases in mutation frequencies related to small colony growth, whereas any significant mutation frequency was not observed in absence of S9 mix. From these results, it is conclusively suggested that dimethyl isophthalate may be a clastogen rather than a point mutagen.