• Journal of Sensor Science and Technology
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• v.18 no.2
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• pp.160-167
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• 2009

In this study, secondary antibody-containing quartz crystal microbalance(QCM) sensor chip was prepared and utilized for the detection of human and bovine haptoglobin. Anti-goat immunoglobulin G antibody, which is a secondary antibody capable of capturing primary antibodies raised in goat, was immobilized through the reaction between hydrazide and aldehyde group prepared on the QCM surface and antibody respectively. The resulting sensor chip showed higher stability in the repeated surface regeneration with acidic dissociation solution as well as requiring lower amount of primary antibody when compared to the protein G sensor chip. The secondary antibody sensor chip was applied for the estimation of bovine and human haptoglobin.

• Korean Journal of Animal Reproduction
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• v.10 no.2
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• pp.168-174
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• 1986

These experiments were carried out to clarify the optimalconditions and interspecific cross reaction of H-Y antibody activity. H-Y antiserum was prepared in inbred SD female rats and Balb/c female mice by repeated immunization of rat newborn testis homogemate, rat and mouse spleen cells obtained from males of same strain. The activity of H-Y antibody in antiserum was tested by ELISA and biological tests. The cross reactivity of H-Y antibody was confirmed by culturing mouse and rabbit embryos in medium containing H-Y antibody and complement obtained from rat and guinea pig, respectively. The optimal condition for the activity of H-Y antibody was also investigated by culturing embryos in medium with different pH and complement concentration. The results obtained in these experiments were summarized as follows: 1. The formation rates of H-Y antibody in rats immunized with newborn testis and spleen cell were 40.0 and 50.0% respectively, and that in mouse immunized with spleen cell was 48.4%. 2. The activity of H-Y antibody was not affected by pH in range of 6.5 to 8.0, and the same was true for the relative concentration of complement to the H-Y antibody. 3. Minimum time needed for the activity of H-Y antibody was confirmed to be 0.5 to 1 hour and 24 to 48 hours respectively for the zona free embryos and intact embryos. 4. When mouse and rabbit embryos were treated with H-Y antibody obtained from rat, 46.4 and 54.8% of embryos were retarded or destroyed. From these results it could be said that H-Y antibody had strong interspecific cross reactivity.

• The Journal of the Korean Society for Microbiology
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• v.6 no.1
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• pp.29-40
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• 1971

Various kinds of antibiotics are generally believed to have inhibitory effects on the antibody response. However, as polymyxin B which belongs to the cyclic polypeptide group of antibiotic was found to have some enhancing effects on the antibody response of rabbits to enterobacterial common antigen(CA) under specified conditions, experiments were carried out on this problem with the following results. 1. When mixture of polymyxin B and CA derived from Salmonella typhimurium(STM) was treated 30 minutes at $37^{\circ}C$ and injected three times into rabbits by intravenous route, the antibody response to CA was weaker than rabbits injected CA only. 2. Mixture of polymyxin B and CA showed a marked antibody production when injected into rabbits primed with small amounts of heat-extracted antigen of STM, while the injection of CA alone showed low titers of response. 3. Mixture of polymyxin B and heat-extracted CA-containing antigen of Escherichia coli 014 also showed a increased antibody production than CA alone in rabbits primed with antigen of STM. 4. The effect of polymyxin B appeared in different ways. This antibiotic did not enhance the CA antibody response in rabbits primed with small amounts of E. coli 0111 and 055, but enhance in rabbits primed with Shigella flexneri. 5. No enhancing effect on the antibody response was observed by polymyxin B in rabbits primed with CA. 6. No enhancing effect on the antibody response was also noted in rabbits primed with STM antigen in case polymyxin B and CA were administered simultaneously but in veins of different places. 7. Bacitracin did not enhance the CA antibody response in primed rabbits with STM antigen, but neomycin slightly enhance the response. 8. Lipopolysaccharide showed no priming effect on the CA antibody response, and no enhancement of the CA antibody response in rabbits printed with STM. 9. The priming effect of STM antigen against CA antibody response was very weak as compared with the effect of CA derived from STM antigen.

• Biomolecules & Therapeutics
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• v.29 no.2
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• pp.166-174
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• 2021

Multiple myeloma is a malignant cancer of plasma cells. Despite recent progress with immunomodulatory drugs and proteasome inhibitors, it remains an incurable disease that requires other strategies to overcome its recurrence and non-response. Based on the high expression levels of programmed death-ligand 1 (PD-L1) in human multiple myeloma isolated from bone marrow and the murine myeloma cell lines, NS-1 and MOPC-315, we propose PD-L1 molecule as a target of anti-multiple myeloma therapy. We developed a novel anti-PD-L1 antibody containing a murine immunoglobulin G subclass 2a (IgG2a) fragment crystallizable (Fc) domain that can induce antibody-dependent cellular cytotoxicity. The newly developed anti-PD-L1 antibody showed significant antitumor effects against multiple myeloma in mice subcutaneously, intraperitoneally, or intravenously inoculated with NS-1 and MOPC-315 cells. The anti-PD-L1 effects on multiple myeloma may be related to a decrease in the immunosuppressive myeloid-derived suppressor cells (MDSCs), but there were no changes in the splenic MDSCs after combined treatment with lenalidomide and the anti-PD-L1 antibody. Interestingly, the newly developed anti-PD-L1 antibody can induce antibody-dependent cellular cytotoxicity in the myeloma cells, which differs from the existing anti-PD-L1 antibodies. Collectively, we have developed a new anti-PD-L1 antibody that binds to mouse and human PD-L1 and demonstrated the antitumor effects of the antibody in several syngeneic murine myeloma models. Thus, PD-L1 is a promising target to treat multiple myeloma, and the novel anti-PD-L1 antibody may be an effective anti-myeloma drug via antibody-dependent cellular cytotoxicity effects.

• The Journal of the Korean Society for Microbiology
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• v.3 no.1
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• pp.43-49
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• 1968

Japanese encephalitis(JE) shows its explosive epidemicity in the temperate zone of Asia but little is known on the overwintering mechanism. One of the hypotheses on the overwintering mechanism is that the virus overwinters in the hibernating animals. There has been no report on the proliferation of JE virus(JEV) or antibody formation in the snakes. The purpose of this experiment is to explore the mutual relationship between JEV and snake and to clarify whether JEV proliferates and induce antibody formation in snakes. Three species of non-poisonous common snakes were employed. Precipitation test was carried out after injecting calf serum and, HI and neutralization tests were done by injecting JEV into the snakes. The gamma globulin fraction of pre- and post-injection serum were compared by paper chromatography. According to the results, precipitating antibody reaction to calf serum could be observed only at $4^{\circ}C$. It was failed to demonstrate HI antibody formation but neutralizing antibody could be detected in one of the 9 snakes. Although antibody could not be detected in test-tube, tile result of paper chromatography shows the remarkable increase of gamma globulin fraction after the injection. Above results are strongly indicating the antibody formation in the snakes.

• Molecules and Cells
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• v.40 no.9
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• pp.655-666
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• 2017

We constructed a large $na{\ddot{i}}ve$ human Fab library ($3{\times}10^{10}$ colonies) from the lymphocytes of 809 human donors, assessed available diversities of the heavy-chain variable (VH) and ${\kappa}$ light-chain variable (VK) domain repertoires, and validated the library by selecting Fabs against 10 therapeutically relevant antigens by phage display. We obtained a database of unique 7,373 VH and 41,804 VK sequences by 454 pyrosequencing, and analyzed the repertoires. The distribution of VH and VK subfamilies and germline genes in our antibody repertoires slightly differed from those in earlier published natural antibody libraries. The frequency of somatic hypermutations (SHMs) in heavy-chain complementarity determining region (HCDR)1 and HCDR2 are higher compared with the natural IgM repertoire. Analysis of position-specific SHMs in CDRs indicates that asparagine, threonine, arginine, aspartate and phenylalanine are the most frequent non-germline residues on the antibody-antigen interface and are converted mostly from the germline residues, which are highly represented in germline SHM hotspots. The amino acid composition and length-dependent changes in amino acid frequencies of HCDR3 are similar to those in previous reports, except that frequencies of aspartate and phenylalanine are a little higher in our repertoire. Taken together, the results show that this antibody library shares common features of natural antibody repertoires and also has unique features. The antibody library will be useful in the generation of human antibodies against diverse antigens, and the information about the diversity of natural antibody repertoires will be valuable in the future design of synthetic human antibody libraries with high functional diversity.

• Molecules and Cells
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• v.27 no.3
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• pp.313-319
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• 2009

The dual-vector system-II (DVS-II), which allows efficient display of Fab antibodies on phage, has been reported previously, but its practical applicability in a phage-displayed antibody library has not been verified. To resolve this issue, we created two small combinatorial human Fab antibody libraries using the DVS-II, and isolation of target-specific antibodies was attempted. Biopanning of one antibody library, termed DVFAB-1L library, which has a $1.3{\times}10^7$ combinatorial antibody complexity, against fluorescein-BSA resulted in successful isolation of human Fab clones specific for the antigen despite the presence of only a single light chain in the library. By using the unique feature of the DVS-II, an antibody library of a larger size, named DVFAB-131L, which has a $1.5{\times}10^9$ combinatorial antibody complexity, was also generated in a rapid manner by combining $1.3{\times}10^7$ heavy chains and 131 light chains and more diverse anti-fluorescein-BSA Fab antibody clones were successfully obtained. Our results demonstrate that the DVS-II can be applied readily in creating phage-displayed antibody libraries with much less effort, and target-specific antibody clones can be isolated reliably via light chain promiscuity of antibody molecules.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.73-81
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• 1997

Diphtheria was the world-spread, respiratory infectious disease in the past. But after developing the diphtheria toxoid, diphtheria vaccine, composed of diphtheria toxoid, is generalized, so prevalence of diphtheria is sharply dropped. But diphtheria is come back in NIS(New Independent States) in 1990s. It is believed that recurrence of diphtheria is mainly due to shortage of protective diphtheria antibody titer in adults. And it is related to 70% prevalence in adults, not in children. Considering this changing environment, this study was designed to research the diphtheria antibody titer of whole population and existence of titer difference by sex. Also it was studied whether ELISA has fitness as determination method of diphtheria antibody titer compared with neutralization method on microcell culture. This study was done to 277 samples of three hospitals in Seoul area, and sera was tested by neutralization method on microcell culture and ELISA method. The results of this study were as follows 1) Of this studied population, 31.05% had an antibody titer below the protective level (<0.01 IU/ml), 40.79% had a titer of a relative degree of protection (0.01-0.09 IU/ml) and 28.16% had a reliable degree of protection ($\geq$0.1 IU/ml). Therefore, 68.95% had a basic protective antibody titer level. 2) 20-40 age group showed the lowest diphtheria antibody titer among the studied population. 3) GMT of diphtheria antibody titer was the highest in the children. But, after child period, GMT was fallen. Standard deviation value was the lowest in older group. 4) Protective level of diphtheria antibody titer of male was slightly higher than female (70.94% vs 66.66%). But this difference was not statistically significant. 5) Diphtheria antibody titer by ELISA method was wholly higher than by neutralization method on microcell culture. Compared the two results by ELISA and neutralization, the regression coefficient was 0.38. And in titer, which was obtained by ELISA method, false-positive results was abundant.

• Fisheries and Aquatic Sciences
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• v.4 no.1
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• pp.32-38
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• 2001

Several molecular biological techniques have been used to detect virus rapidly and accurately, but these methods have limitations in the early stage of viral infection with very low concentration of virus. We compared the detection limits of IMS-PCR, Western blot and ELISA with infectious hematopoietic necrosis virus OHNV). Four antibodies, rabbit anti-IHNV polyclonal antibody, anti-IHNV nucleocapsid protein monoclonal antibody, anti-IHNV nucleocapsid protein polyclonal antibody, and anti-IHNV glycoprotein polyclonal antibody, were tested to find out the most effective antibody for each method. The detection limit with IMS- PCR was $2\times10^6$ pfu when the viral RNA was extracted before RT-PCR. In the western blot with rabbit anti­IHNV polyclonal antibody one pfu of virus could be detected. In ELISA, 10 pfu of virus particles were detected with the same antibody.

• Korean Journal of Animal Reproduction
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• v.14 no.3
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• pp.157-164
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• 1990

Anti-progesterone monoclonal antibody injected intraperitonially as a single dose(100$\mu\textrm{g}$) 48hours post coitum(p.c.) almostly blocked pregnancy in ICR mice. The blocking rate of pregnancy in mice treated with antibody were decreased proportionally according to dose of antibody injected ; the rate were 60%, 57% and 17% as the antibody of 10$\mu\textrm{g}$, 50$\mu\textrm{g}$ and 100$\mu\textrm{g}$ were injected respectively. Blood serum progesterone concentration was greatly increased(21 times) after treatment(100$\mu\textrm{g}$), by virtue of high-affinity binding by antibody in circulation of non-pregnant mice in coompared with that of control group at day 10 p.c.. The concentration was about 1.6 times higher in the pregnant mice than in the non-pregnant mice in antibody treated group. In control group, the progesterone concentration was over 7 times higher in the pregnant mice than in non-pregnant mice at day 5 p.c..