• Microbiology and Biotechnology Letters
• /
• v.46 no.3
• /
• pp.269-276
• /
• 2018

Rabies virus (RABV)-specific antibodies in animals and humans are measured using standard methods such as fluorescent antibody virus neutralization (FAVN) tests and rapid fluorescent focus inhibition tests, which are based on cell culture systems. An alternative assay that is safe and easy to perform is required for rapid sero-surveillance following mass vaccination of animals. Two purified monoclonal antibodies (4G36 and B2H17) against RABV were selected as capture and detection antibodies, respectively. A genetically modified RABV, the ERAGS strain, was propagated and concentrated by polyethylene glycol precipitation. Optimal conditions for the RABV antigen, antibodies, and serum dilution for a blocking enzymelinked immune sorbent assay (B-ELISA) were established. We evaluated the sensitivity, specificity, and accuracy of the B-ELISA using serum samples from 138 dogs, 71 raccoon dogs, and 25 cats. The B-ELISA showed a diagnostic sensitivity of 95.8-96.3%, specificity of 91.3-100%, and accuracy of 96.0-97.2% compared to the FAVN test. These results suggest that the B-ELISA is useful for sero-surveillance of RABV in dogs, raccoon dogs, and cats.

• Parasites, Hosts and Diseases
• /
• v.50 no.3
• /
• pp.233-238
• /
• 2012

The precise diagnosis of the acute toxoplasmosis in pregnant women and immunocompromsied patients has critical importance. Most of the commercially available assays use the whole Toxoplasma soluble extract as the antigen. However, the assays currently available for the detection of specific anti-Toxoplasma antibodies may vary in their abilities to detect serum immunoglobulins, due to the lack of a purified standardized antigen. The aim of this study was production and evaluation of the usefulness of the recombinant Toxoplasma gondii GRA7 antigen for the serodiagnosis of Toxoplasma gondii IgM and IgG by ELISA. A total of 70 T. gondii IgM positive sera, 74 T. gondii IgG positive sera, and 60 sera from subjects who were not infected with T. gondii were examined. These sera were shown different absorbance values in ELISA test. To control the specificity of the rGRA7 other parasitic diseases, for example, echinococcosis, malaria, leishmaniasis, fascioliasis, and strongyloidiasis were tested of which none showed positive results. Sensitivity and specificity of the generated recombinant IgG ELISA in comparison with commercial ELISA (com ELISA) were 89% and 90%, and the sensitivity and specificity of the generated recombinant IgM ELISA were 96% and 90%, respectively. The results obtained here show that this antigen is useful for diagnostic purposes.

• Journal of Environmental Health Sciences
• /
• v.34 no.5
• /
• pp.369-373
• /
• 2008

The indoor environment is an important source of exposure to various aeroallergens and pathogenic microorganism. It has been shown that exposure to aeroallergens enhances the risk of indoor inhabitants developing asthma. Since the skin prick test, a typical clinical method for identification of subjects positive to allergens, can rarely cause fatal or non-fatal reactions in susceptible persons, an in vitro assay such as ELISA using serum has been considered for testing positivity against various allergens. We evaluated the validity of a serum ELISA kit for screening positive subjects to major aeroallergens including Dermatophagoides farinae, Dermatophagoides pteronyssinus, cockroach, Alternaria, Cladosporium, Aspergillus, Penicillium, dog hair, cat fur, mugwort, and ragweed. The ELISA results were compared with the skin prick test results, and sensitivity, specificity, and overall accuracy were calculated to each allergen. Higher sensitivities were obtained from D. farinae, (77.8%) and D. pteronyssinus (69.2%), but sensitivities to Aspergillus, Penicillium, dog hair, cat fur, and ragweed were very low down to 0%. Specificity ranged from 88.7% (cat fur) to 100% (mugwort and ragweed). Overall the accuracy of the serum ELISA kit was relatively high, in that the lowest was 85.1% for cat fur and the highest was 98.6% for Alternaria, Cladosporium, and ragweed. Considering specificity and overall accuracy for the serum ELISA kit, it may be considered reliable. However, when the kit is used for screening purpose, positivity to aeroallergens should be carefully determined since sensitivity for the kit is low.

• Tuberculosis and Respiratory Diseases
• /
• v.47 no.6
• /
• pp.757-767
• /
• 1999

Background: Diagnosis by smear and/or cultures of the Mycobacterium tuberculosis from body fluid or biopsy specimen is "Gold standard". However the sensitivity of the direct microscopy is relatively low and culture of mycobacteria is time consuming. Despite an explosion in the techniques of rapid identification of mycobacteria by molecular genetic means, it is laborious and expensive and then rapid, inexpensive serodiagnosis is interested in diagnosis of tuberculosis. But sensitivity and specificity of known serologic antigen is not full sufficient level and then new antigen develop and combination cocktails of new developed antigens by ELISA are needed. Method: To compare the efficacy of different mycobacterial specific antigen and to assess the applicability of the combination of several different antigens in the diagnosis of tuberculosis, five ELISA tests derived 14KDa, 16KDa, 19KDa, 23KDa, 38KDa were evaluated in 57 active pulmonary patient and 24 inactive post-therapy follow up patient and 48 normal control. Results: The optical densities of ELISA test with 14KDa, 16KDa, 19KDa, 23KDa, 38KDa were significantly higher in active tuberculosis cases than in normal control(P<0.001, P<0.001, P<0.027, P<0.001, P<0.001) and those with 16KDa, 38KDa were significant higher in active tuberculosis cases than in inactive post-therapy follow up cases(P<0.01. P<0.001) and those of 14KDa, 16KDa, 23KDa, 38KDa were significant higher in inactive post-therapy follow up cases than in normal control(P<0.008. P<0.01. P<0.006. P<0.001). The sensitivity of 14KDa, 16KDa, 19KDa, 23KDa, 38KDa in active pulmonary patient cases was 42.1%, 43.9%, 15.8%, 28.0%, 70.2%, respectively and the specificity of 14KDa, 16KDa, 19KDa, 23KDa, 38KDa in active pulmonary patient cases was 95.8%, 95.8%, 91.7%, 89.6%, 93.8%, respectively. The sensitivity and specificity of combination 38KDa with 16KDa was 87% and 93.7%. Conclusion: The sensitivity and specificity of new antigens for serodiagnosis of the tuberculosis still remains limited at around 70%, which makes its a poor diagnostic tool for disease confirmation. A combination of cocktail antigens provided by cut-off value adjustment for serodiagnosis of tuberculosis some improved diagnostic yield than single antigen serologic test.

• Korean Journal of Clinical Laboratory Science
• /
• v.39 no.1
• /
• pp.42-48
• /
• 2007

This study was carried out to review and evaluate anti-CCP ELISA assay for diagnostic in RA patients from an early arthritis clinic (EAC). The subjects were obtained from patients visiting the outpatient clinic of the Dept. of Rhumatology med.of P hospital in Daegu, during 6 months from July 1, 2006 to December 31, 2006. The subjects were 140 cases : 80 cases from RA patients (60 women and 20 men; mean age 58 years; range, 32-68 years) confirmed by clinical diagnostic. 39 cases of these RA patients were classified as having early RA (EAC). 50 cases (non-RA) did not fulfill the criteria for RA, and 10 cases were from healthy individuals. We performed the analysis with solid phase-ELISA method (ETI-max3000, Diasorin; Italy) for anti-CCP and Nephelometry assay (Roche/Hitachi 902 analyzer; USA) for RF. The results obtained were summarized as follows ; anti-CCP ELISA is more specific than RF Nephelometry assay (specificity 94% vs 90%) to diagnose RA patients with suspected EAC (early arthritis clinic). The combination test "anti-CCP and RF" had a very high specificity (specificity 98.3%, PPV; RA group 96%, EAC 95%), the difference was statistically significant (p<0.05). Anti-CCP ELISA had more sensitivity in EAC (Early arthritis clinic) patients than chronic RA patients (sensitivity 64% vs 24%, respectively), anti-CCP of RA group and EAC group was more specific than RF (anti-CCP PPV; 92%, 89% vs 89%, 81% respectively), the difference was statistically significant (p<0.05). The difference of antibody concetration between anti-CCP and RF for RA and the control group is statistically significant (p<0.05). In conclusion, anti-CCP ELISA testing may be useful if performed concomitantly with RF Nephelometry assay to diagnose RA patients with suspected EAC (early arthritis clinic).

• Parasites, Hosts and Diseases
• /
• v.52 no.4
• /
• pp.377-381
• /
• 2014

Microscopy is considered as the gold standard for malaria diagnosis although its wide application is limited by the requirement of highly experienced microscopists. PCR and serological tests provide efficient diagnostic performance and have been applied for malaria diagnosis and research. The aim of this study was to investigate the diagnostic performance of nested PCR and a recently developed an ELISA-based new rapid diagnosis test (RDT), NovaLisa test kit, for diagnosis of malaria infection, using microscopic method as the gold standard. The performance of nested-PCR as a malaria diagnostic tool is excellent with respect to its high accuracy, sensitivity, specificity, and ability to discriminate Plasmodium species. The sensitivity and specificity of nested-PCR compared with the microscopic method for detection of Plasmodium falciparum, Plasmodium vivax, and P. falciparum/P. vivax mixed infection were 71.4 vs 100%, 100 vs 98.7%, and 100 vs 95.0%, respectively. The sensitivity and specificity of the ELISA-based NovaLisa test kit compared with the microscopic method for detection of Plasmodium genus were 89.0 vs 91.6%, respectively. NovaLisa test kit provided comparable diagnostic performance. Its relatively low cost, simplicity, and rapidity enables large scale field application.

• Parasites, Hosts and Diseases
• /
• v.51 no.4
• /
• pp.433-440
• /
• 2013

Toxocariasis is a worldwide zoonosis caused by larvae of ascarid nematodes of dogs or cats, Toxocara canis or T. cati. Diagnosis of human toxocariasis currently relies on serology that uses T. canis excretory-secretory antigen to detect specific IgG antibodies by ELISA. We investigated the serodiagnostic efficacy of ELISA using crude antigen of T. canis larvae (TCLA). Serum specimens of 64 clinically confirmed toxocariasis, 115 healthy controls, and 119 other tissue-invading helminthiases were screened by ELISA using TCLA. The ELISA using TCLA showed 92.2% (59/64 patient samples) sensitivity and 86.6% (103/119) specificity. Its positive diagnostic predictivity was 78.7% and negative predictivity was 97.8%. No serum of healthy controls reacted but that of anisakiasis (45.5%), gnathostomiasis (19.2%), clonorchiasis (15.8%), sparganosis (11.1%), and cysticercosis (6.3%) cross-reacted. Immunoblot analysis on TCLA recognized antigenic proteins of 28- and 30-kDa bands in their dominant protein quantity and strong blotting reactivity. The present results indicate that the ELISA using our TCLA antigen is acceptable by the sensitivity and specificity for serodiagnosis of human toxocariasis. ELISA with TCLA is recommended to make differential diagnosis for patients with any sign of organ infiltration and eosinophilia.

• Parasites, Hosts and Diseases
• /
• v.47 no.4
• /
• pp.427-429
• /
• 2009

To establish a definite diagnosis for pulmonary hydatid disease, combination of radiology and serology is useful. In this study, 19 preoperative sera from patients with surgically confirmed pulmonary hydatidosis, 40 sera from patients with other parasitosis and pulmonary diseases, and 20 sera from healthy donors were evaluated using 4 different serological tests, i.e., the commercial ELISA (ELISA-kit) test, the ELISA (ELISA-lab) test prepared in our laboratory, the commercial indirect hemagglutination assay kit (IHA-kit) test, and the IHA test using sensitized sheep red blood cells with tannic acid (IHA-TA). The ELISA-kit was the most sensitive (84.2%) and the most specific test (100.0%). The ELISA-kit also demonstrated the highest positive (100.0%) and negative (95.2%) predictive values. The sensitivity of the ELISA-lab test, that we prepared, was found to be 73.6%, whereas the IHA-kit test and the IHA-TA test were found to be 73.6% and 68.4%, respectively. The specificity of these tests was 96.6%, 98.3%, and 83.3%, respectively. When all 4 tests were assessed together, it was found that the sensitivity had risen to 94.7%. When the ELISA-kit was assessed with the IHA-kit and IHA-TA together, it was found that the sensitivity was 89.5% and 84.2%, respectively. Likewise, the combination of the ELISA-lab and IHA-kit or IHA-TA allowed us to achieve a sensitivity of 84.2% in cases of pulmonary echinococcosis. In conclusion, the diagnosis would be imminent if least 2 tests were applied together.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.8
• /
• pp.1116-1119
• /
• 2002

Monoclonal antibodies have been generated against a generic hapten, ο,ο-diethyl ο-(5-carboxy-2-fluorophenyl) phosphorothioate, for the determination of organophosphorus (OP) pesticides in a class-specific manner. In an indirect competitive enzyme-linked immunosorbent assay (ELISA) format, employing a heterologous coating antigen, these monoclonal antibodies showed desirable properties for use in the class-specific determination, i.e., broad specificity and high sensitivity. The IC50 values of four commonly used ο,ο-diethyl OP pesticides were fairly uniform ranging from 0.1 to 0.3 ㎛/mL. The IC50 values of three ο,ο-dimethyl derivatives were between 0.3 and 1.4 ㎛/mL. These values, together with the limits of detection (LOD), were better, in terms of the specificity and sensitivity, compared with the values obtained previously with polyclonal antibodies.

• Korean Journal of Veterinary Service
• /
• v.31 no.3
• /
• pp.315-329
• /
• 2008

A total of 710 bovine serum samples which are composed 532 bovine serum samples showed negative reaction and 178 bovine serum samples showed positive reaction with tube agglutination test (TAT) from North area of Gyeong-nam, Korea were tested using all the 3 assays which are Rose-Bengal test(RBT), tube agglutination test (TAT) and enzyme-linked immunosorbent assay (ELISA, two types) and analyzed for evaluation of specificity, sensitivity, reproducibility and predictive value. In the comparison of serum antibody titer agglutination test, RBT showed almost agreement with TAT. In the comparison of TAT and two types of ELISA method, they showed difference in specificity and sensitivity about 5%. But there is no significant difference in detecting sensitivity between two types of ELISA method and TAT. In serologic tests for bovine brucellosis, the new assay ELISA would be a good candidate for serologic survey for bovine brucellosis in Korea because it is efficient in detecting many test samples quickly. But the serum agglutination tests (RBT, TAT) are more economical and easy assay for detection. In the test of comparison of antibody titer between first day of finding and 10 days after finding by TAT, there was no change in 55% (76/139) of positive cattle.