• Parasites, Hosts and Diseases
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• v.47 no.2
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• pp.153-157
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• 2009

Diagnosis of hydatidosis is based on immunodiagnostic methods along with radiological and ultrasound examinations. The objectives of the present study were to develop a specific and simple antigen-based ELISA method for diagnosis of hydatidosis and compare it with antibody detection method. The subjects in this study included 89 patients in the following groups: surgically confirmed hydatidosis patients (35 cases), control with other parasitic diseases (29 cases), and healthy controls (25 cases). Hyperimmune serum was raised against hydatid cyst fluid in rabbits. Anti-hydatid cyst IgG was purified by affinity chromatography using protein A column and labeled with horseradish peroxidase. Collected sera were assessed for hydatid cyst antigens and antibody by ELISA. Circulating hydatid antigen was found in 9 out of 35 patients with surgically confirmed hydatidosis. A sensitivity of 25.7% and a specificity of 98.0% were calculated for the antigen detection assay. Antibody detection by indirect ELISA, using antigen B, showed that 94.2% of patients (33 cases) have anti-hydatid cyst antibodies in their serum while cross reaction was noted in a few of non-hydatidosis patients. A sensitivity of 94.2% and specificity of 81.6% were found for the antibody detection assay. Findings of this study indicated that antibody detection assay is a sensitive approach for diagnosis of hydatid cyst while antigen detection assay might be a useful approach for assessment of the efficacy of treatment especially after removal of the cyst.

• Journal of Microbiology
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• v.45 no.6
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• pp.547-552
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• 2007

Previously, we generated monoclonal antibodies (MAbs) that bound to the surface of human embryonic stem cells (hESCs) in an attempt to discover new hESC-specific surface markers. In this study, MAb 47-235 (IgG1, ${\kappa}$) was selected for further characterization. The MAb bound to the surface of undifferentiated hESCs but did not bind to mouse ESCs or mouse embryonic fibroblast cells in flow cytometric analysis. The antibody immunoprecipitated a 47 kDa protein from the lysates of cell surface-biotinylated hESCs. Identification of the protein by quadrupole time of flight tandem mass spectrometry revealed that 47-235 binds to Ag 243-5 protein of Mycoplasma arginini. BM-Cyclin treatment of the hESCs that reacted with 47-235 resulted in loss of mycoplasma DNA and the reactivity to 47-235. Nevertheless, the hESCs that were reactive to 47-235 maintained self-renewal and pluripotency and thus could be differentiated into three embryonic germ layers.

• Biomedical Science Letters
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• v.12 no.1
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• pp.35-42
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• 2006

Alloimmunization to red blood cell (RBC) antigens may cause a delayed hemolytic transfusion reactions (DHTR) and a delayed serologic transfusion reactions (DSTR). In the present study, the frequency of alloimmunization and its clinical significance were evaluated. Also, transfusions were correlated with antibody formation. Alloimmunization rate was 0.63%. Alloimmunization rate in multiple transfused patients was 24.5%. The most common clinically significant alloantibodies of alloimmunized patients were found to be Rh antibodies (52.6%). Nine patients out of 38 (23.7%) became undetectable after the first detection. To be positive at antibody screening test after RBC transfusion was mean transfused numbers: 3.7 units, mean transfused periods: 56 days, mean transfused frequencies: 1.7 times. The results from antibody specificity and RBC transfusions were comparatively analyzed and it shows that Rh system antibodies were longer than other antibodies (P<0.05). In case of disease group, malignant diseases was longer than other diseases (P<0.05). In order to prevent the formation of RBC alloimmunization, irregular antibody screening tests were performed at propriety intervals in multiple transfused patients.

• BMB Reports
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• v.37 no.5
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• pp.556-564
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• 2004

A recombinant Fab monoclonal antibody (Fab) C37, previously obtained by phage display and biopanning of a random antibody fragment library against Burkholderia pseudomallei protease, was expressed in different strains of Escherichia coli. E. coli strain HB2151 was deemed a more suitable host for Fab expression than other E. coli strains when grown in media supplemented with 0.2% glycerol. The expressed Fab fragment was purified by affinity chromatography on a Protein G-Sepharose column, and the specificity of the recombinant Fab C37 towards B. pseudomallei protease was proven by Western blotting, enzyme-linked immunosorbent assay (ELISA) and by proteolytic activity neutralization. In addition, polyclonal antibodies against B. pseudomallei protease were produced in rabbits immunized with the protease. These were isolated from high titer serum by affinity chromatography on recombinant-Protein A-Sepharose. Purified polyclonal antibody specificity towards B. pseudomallei protease was proven by Western blotting and ELISA.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.191-197
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• 2005

An immunochromatographic (IC) strip for the rapid detection of Salmonella spp. in the enriched sample was developed. Affinity purified Salmonella polyclonal antibody was conjugated with 40 nm colloidal gold particles which were prepared by citrate method in our laboratory. The antigen-antibody-gold complex was captured by Salmonella antibody attached to test line of nitrocellulose membrane during the capillary migration of sample. Specificity of the IC strip was calculated to be 100% (12/12) and sensitivity was 97.6% (41/42) in the test with pure cultured bacteria. Salmonella was artificially inoculated into raw pork macerated with enrichment broth. And then it was 10-fold diluted from $5.2{\times}10^{8}CFU/ml$ to 5.2 CFU/ml. The IC strip could detect $5.2{\times}10^{6}CFU/ml$ before enrichment. However, the lowest limit of detection was 5.2 CFU/ml after overnight incubation. The results indicated that the IC assay was a rapid, economical and simple method with high specificity and sensitivity for the detection of Salmonella spp. without using any equipment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s01
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• pp.48-54
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• 1989

An immunoassay techniques using monoclonal antibodies have been developed of the quantitative analysis of endogenous hormones in plants. In order to be useful for immunoassay, both a high degree of specificity and a high affinity are required. A system is described for production of hybridomas which secrete antibodies against the plant hormone. Using the system we were able to produce hybridmas with the desired antibody specificity by cell fusion and culture method. For a number of obvious reasons, monoclonal antibodies(mAb) were superior to polyclonal antibodies.

• Journal of Microbiology
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• v.45 no.6
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• pp.528-533
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• 2007

In a previous study we generated an anti-Hepatitis B Virus (HBV) preS1 humanized antibody (HzKR127) that showed in vivo HBV-neutralizing activity in chimpanzees. However, the antigen-binding affinity of the humanized antibody may not be sufficient for clinical use and thus affinity maturation is required for better therapeutic efficacy. In this study, phage display technique was employed to increase the affinity of HzKR127. All six amino acid residues (Glu95-Tyr96-Asp97-Glu98-Ala99-Tyr100) in the heavy (H) chain complementary-determining region 3 (HCDR3) of HzKR127 were randomized and phage-displayed single chain Fv (scFv) library was constructed. After three rounds of panning, 12 different clones exhibiting higher antigen-binding activity than the wild type ScFv were selected and their antigen-binding specificity for the preS1 confirmed. Subsequently, five ScFv clones were converted to whole IgG and subjected to affinity determination. The results showed that two clones (B3 and A19) exhibited an approximately 6 fold higher affinities than that of HzKR127. The affinity-matured humanized antibodies may be useful in anti-HBV immunotherapy.

• Korean Journal of Veterinary Research
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• v.13 no.1
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• pp.39-46
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• 1973

Cultural method, dark field microscopy & fluorescent antibody technique were compared for their sensitivity of the detection of leptospires from experimentally infected mice. Two groups of mice were infected with L. icterohemorrhagiae (M20) and L. australis (Ballico), and the infected blood, urine and a number of organs were subjected to the bacterial isolation. The results obtained were summarized as follows: 1. L. icterohemorrhagiae (M20) and L. australis (Ballico) in blood, urine and various tissues of experimentally infected mice were detected with a negrigible non specificity, by the fluorescent antibody technique. 2. The fluorescent antibody technique, as applied to detection of leptospires in blood, urine and various infected tissue, proved to be better than cultural method and dark-field microscopy. 3. Early detection of leptospires by fluorescent antibody technique were possible in blood at 2 days after inoculation, whereas detection of organisms in liver, spleen, lung and kidney were observed later. By means of fluorescent antibody technique, the detection of leptospires in kidney and urine was possible up to 34 days postinoculation, whereas those in other parts were impossible. 4. Fluorescent antibody reaction of leptospires were highly specific to homologous antigen rather than to heterologous one. 5. Fluorescent antibody technique may be of value in the application for the demonstration of leptospira from clinical specimens.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1811-1814
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• 2007

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.701-705
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• 2003

Performance of an immunosensor can usually be assessed in terms of its analytical sensitivity and specificity. Sensitivity, i.e., the detection limit of analyte, is particularly determined by the amount of analyte molecules bound to the capture antibody immobilized onto a solid surface. In order to increase the binding complexes, we have investigated an immobilization method of antibody allowing for a molecular arrangement of the protein on a selective surface of a nano-patterned solid substrate. This has not been accomplished only by a surface treatment with a chemical, but also by fragmentation of immunoglobulin. Such approach would offer a protocol of antibody immobilization for the construction of nano-immunosensor and eventually improve the sensitivity of detection.