• 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..

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

• Microbiology and Biotechnology Letters
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• v.19 no.3
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• pp.272-280
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• 1991

The effect of media feeding rate on cell growth and monoclonal antibody production in the fed-batch culture ot hybridoma A4W was studied. In the batch culture, the highest specific antibody production rate was observed at the begining of the culture period but its value tended to decrease rapidly with the culture time. The final antibody concentration and volumetric productivity was 65 $\mu g$/ml and 13 mg Mab/l/day, respectively. In the fed-batch culture, the specific antibody production rate, $q_p$ rebounded sharply within a few hours after the media feeding was started and it remained high until the end of culture if the media feeding was continued. The final antibody concentration was 220 $\mu g$/ml and the volumetric productivity was 45.1 mg/l/day. Further increase in final antibody concentration was achieved by applying a modified media of which component was fortified with glucose and glutamine, hence the final antibody concentration in this case was 270 $\mu g$/ml and the volumetric productivity was 51.8 mg/lday, which is as four tinlcs as high cuixparinf! to that of batch culture.

• KSBB Journal
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• v.15 no.5
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• pp.482-488
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• 2000

The Fab fraction of PDC-E2 specific human monoclonal antibody was produced using recombinant E. coli, and the effects of glucose and acetate were investigated to develop an optimal strategy for recombinant human antibody production. Higher glucose concentration in the culture media resulted inn higher cell growth and glucose consumption rate, which in turn resulted in an increased acetate production rate. When glucose was depleted, cells began to consume acetate as an energy source, and this consumption rate depended on the glucose concentration. When the residual glucose concentration was high, the accumulation of acetate was accelerated due to an increase in the acetate production rate and a decrease in the acetate consumption rate. Futhermore, it was found that a high accumulation of acetate, accompanied by a high glucose concentration, inhibited human antibody formation; the critical acetate concentration was $0.6g/\ell$. During production, a high glucose concentration enhanced cell growth, but inhibited antibody formation due to catabolic repression. Therefore, it is important to keep the concentration of both glucose and acetate as low as possible to increase antibody production after induction. Accordingly, it is important to accurately control the concentration of glucose and acetate in the culture media to obtain high cell densities and high productivity levels of recombinant human antibody.

• KSBB Journal
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• v.11 no.4
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• pp.420-430
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• 1996

One-step immuno-chromatography assay system for heat-killed Salmonella typhimurium antigens was developed. Three major components used were a glass fiber membrane (placed at the bottom of the system) with an antibody (specific to the analyse, detection antibody)-gold conjugate deposited in a dry state on the surface, a nitrocellulose membrane (middle) with an antibody (also, specific to the analyse but recognized different epitome: capture antibody) and anti-detection antibody immobilized in spatially separated areas, and a cellulose membrane (top) as absorption pad. These membranes were partially superimposed such that a wicking of aqueous solution containing sample can continuously take place through membranes. Variables that affected the system performance were the concentration of capture antibody, the location on the membrane, inert protein used for blocking of the membrane and for carrying the sample, and the concentration of the gold conjugate. Under optimal conditions, within 15 minutes after absorption of a sample solution from the bottom of the system antigen-antibody complexes of sandwich type were formed on the membrane surface area with immobilized capture antibody and a color signal was generated in proportion to the analyse concentration. The minimum do tection limit of the analyse was $1{\times}106$ Salmonella cells/mL.

• 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.

• Membrane Journal
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• v.30 no.6
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• pp.373-384
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• 2020

Antibody-based therapeutics have been receiving great attention as a representative biopharmaceutical, in which many researches are also carried out for its commercialization. The downstream process is considered an important part of the manufacturing processes of antibody-based therapeutics since it directly affects the performance and stability of products. Ultrafiltration/diafiltration (UF/DF), mostly performed in final step during downstream process, are used for the final concentration and formulation of antibody-based therapeutics. This paper reviewed the major products of the UF membrane, process characteristics, and recent research trends in UF/DF.

• Journal of Information Processing Systems
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• v.15 no.1
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• pp.137-150
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• 2019

Although the research of immune-based anomaly detection technology has made some progress, there are still some defects which have not been solved, such as the loophole problem which leads to low detection rate and high false alarm rate, the exponential relationship between training cost of mature detectors and size of self-antigens. This paper proposed an intrusion detection method based on changes of antibody concentration in immune response to improve and solve existing problems of immune based anomaly detection technology. The method introduces blood relative and blood family to classify antibodies and antigens and simulate correlations between antibodies and antigens. Then, the method establishes dynamic evolution models of antigens and antibodies in intrusion detection. In addition, the method determines concentration changes of antibodies in the immune system drawing the experience of cloud model, and divides the risk levels to guide immune responses. Experimental results show that the method has better detection performance and adaptability than traditional methods.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.293-296
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• 2002

Hyperosmotic pressure increased specific antibody productivity ($q_{Ab}$) of recombinant CHO cells (SH2-0.32) while it depressed cell growth. Thus, the use of hyperosmolar medium did not increase the maximum antibody concentration substantially. To overcome this drawback, the feasibility of biphasic culture strategy was investigated. In the biphasic culture, cells were first cultivated in the standard medium with physiological osmolality(294 mOsm/kg) for cell growth. When cells reached the late exponential phase of growth, the spent standard medium was replaced with the fresh hyperosmolar medium (522 mOsm/kg) for antibody production. The ($q_{Ab}$) in growth phase with the standard medium was 2.1 ${\mu}g/10^6cell/day$ while the ($q_{Ab}$) in antibody production phase with the hyperosmolar medium (522 mOsm/kg) was 11.1 ${\mu}g/10^6cell/day$. Northern blot analysis showed a positive relationship between the relative contenet of Ig mRNA and ($q_{Ab}$), indicating that transcriptional regulation was involved in the response of rCHO cells to hyperosmotic pressure. Due to the enhanced ($q_{Ab}$) and increased cell concentration in biphasic culture, the maximum antibody concentration obtained in biphasic culture with 522 mOsm/kg medium exchange was 161% higher than that obtained in batch culture with the standard medium. Taken together, simple biphasic culture strategy based on hyperosmotic culture for improved foreign protein production from rCHO cells is effective in improving antibody production of rCHO cells.

• KSBB Journal
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• v.10 no.3
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• pp.323-334
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• 1995

The effects of glucose on cell growth kinetics, monoclonal antibody productivity, and cell metabolism or hybridoma cells were investigated. The mouse-mouse hybridoma cell line VIII H-8 producing mouse IgG2a was used as a modal system. Glucose showed substrate inhibition type dependence on specific growth raie. The maximum cell density increased as initial glucose concentration increased up to 4 g/$\ell$. Glucose showed a strong influence on cell death kinetics, and an inverse relationship between specific death rate and glucose concentration was found. Cell viability and monoclonal antibody production increased as initial glucose concentration increased. The specific glucose consumption rate increased with glucose concentration, and cumulative specific lactate production rate increased with increasing initial glucose concentration. The overall kinetics of ammonium ion production was almost invariant with respect to initial glucose concentration, while the cumulative specific ammonium ion production rate was dependent on initial glucose concentration.