Enzyme-linked immunosorbent assay was used to target growth hormone (GH)/insulin growth factor-1 (IGF-1), one of the main regulators of the aging process. Declining levels of total protein and increased levels of glucose in young dogs was observed regardless of their body size. Notably, a significantly high concentration of GH and IGF-1 in the younger dogs compared to the older dogs was found in middle/large-sized dogs. GH and IGF-1 were also found at significantly high levels in large-sized dogs compared to middle-sized dogs, suggesting a similar trend to that of elderly humans. Consequently, glucose, total protein, GH, and IGF-1 were identified as potential biomarkers for regulating the aging process in large/middle-sized dogs. These findings provide an invaluable insight into the mechanism of aging for the field of aging research.]]>
Aged ; Aging ; Animals ; Biomarkers ; Body Size ; Dogs ; Enzyme-Linked Immunosorbent Assay ; Genomic Instability ; Glucose ; Growth Hormone ; Hematologic Tests ; Humans ; Insulin-Like Growth Factor I ; Mammals ; Quality of Life

ELISAs and rapid diagnostic tests (RDTs) are widely used for diagnosing dengue virus (DENV) infection. Using 138 single blood samples, we compared the ability to detect non-structural (NS)-1 antigen and anti-DENV IgM/IgG antibodies among (1) DENV Detect NS1 ELISA, DENV Detect IgM capture ELISA and DENV Detect IgG ELISA (InBios International, Inc.); (2) Anti-Dengue virus IgM Human ELISA and Anti-Dengue virus IgG Human ELISA (Abcam); (3) Dengue virus NS1 ELISA, Anti-Dengue virus ELISA (IgM) and Anti-Dengue virus ELISA (IgG) (Euroimmun); (4) Asan Easy Test Dengue NS1 Ag 100 and Asan Easy Test Dengue IgG/IgM (Asan Pharm); (5) SD BIOLINE Dengue Duo (Standard Diagnostics); and (6) Ichroma Dengue NS1 and Ichroma Dengue IgG/IgM (Boditech Med). For NS1 antigen detection, InBios and Euroimmun showed higher sensitivities (100%) than the RDTs (42.9–64.3%). All tests demonstrated variable sensitivities for IgM (38.1–90.5%) and IgG (65.7–100.0%). InBios and Boditech Med demonstrated higher sensitivity (95.6% and 88.2%, respectively) than the other tests for combined NS1 antigen and IgM antibody. Five NS1 antigen tests had good agreement (92.8–98.6%) without showing positivity for chikungunya. However, all IgG tests demonstrated potential false-positivity with variable ranges. Clinical laboratories should note performance variations across tests and potential cross-reactivity.
Antibodies ; Chungcheongnam-do ; Dengue Virus ; Dengue ; Diagnosis ; Diagnostic Tests, Routine ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunoglobulin G ; Immunoglobulin M

PURPOSE: Foot-and-mouth disease (FMD) and anthrax are important diseases in sheep. Vaccination is a favorable strategy against both infections. Simultaneous administration of vaccines does generally not impede the immune responses of each other, although there are some exceptions, and it may help reduce the labor and costs of vaccination as well as distress on animals. Although oil adjuvant FMD vaccine has been tried with live anthrax vaccine in cattle, there are no reports on the simultaneous use of both vaccines in sheep. MATERIALS AND METHODS: In this study, FMD seronegative sheep were used to investigate the impact of the simultaneous vaccination of FMD and anthrax on FMD antibody titers of sheep. Virus neutralization test and liquid phase blocking enzyme-linked immunosorbent assay were used to determine the antibody response to the FMD vaccine. RESULTS: The results demonstrated that both vaccines can be used simultaneously without any interference with the FMD response. Moreover, the simultaneous administration with anthrax vaccine had a stimulating effect on the early (day 7 post-vaccination) virus neutralization antibody response to the FMD vaccine. CONCLUSION: The simultaneous use of the FMD and anthrax vaccines did not hinder the response to the FMD vaccine in sheep.
Animals ; Anthrax Vaccines ; Anthrax ; Antibody Formation ; Cattle ; Enzyme-Linked Immunosorbent Assay ; Foot-and-Mouth Disease ; Neutralization Tests ; Sheep ; Vaccination ; Vaccines

BACKGROUND: As stated in ‘The Action Strategy for Tuberculosis-Free Korea,’ last March, high-throughput, large-scale analytical instruments for interferon gamma release assays (IGRA) are demanded by many clinical laboratories using the QuantiFERON-TB Gold In-Tube assay (Cellestis/Qiagen, Australia). Agility (Dynex Technologies, USA) is an automated high-throughput enzyme linked immunosorbent assay analyser. The present study aimed to evaluate its accuracy and speed. METHODS: Pooled plasma was prepared using samples obtained after IGRA testing. Analyses of precision, linearity, cut-off evaluation, and comparison with conventional methods were performed for multiple Agility instruments according to the Clinical and Laboratory Standards Institute EP5-A3, EP6-A, EP9-A3 and EP12-A2 guidelines. The turnaround time and throughput were also analysed. RESULTS: The coefficient of variation range was 2.48%–4.0%, 7.01%–11.17%, and 9.69%–14.84% for the repeatability, between-run precision, and between-day precision analyses, respectively. The linearity ranged from 0 to 10.541. Comparison analysis presented a high concordance of Agility with the conventional instrument, DS2 (Dynex Technologies), and manual method for IGRA. The cut-off value of 0.35 IU/mL was well compatible with the C50. It was identified that the C50±20% contained the C5–C95 interval. The average turnaround time was 3.84 hours, from the submission of pre-treated samples to the reporting of results. The throughput was determined to be 290 tests during a routine working time of 8 hours. CONCLUSIONS: Agility showed high precision, linearity, concordance, and had a 2.5 times faster throughput than with the conventional and manual method. It could be useful for large-scale IGRA testing in latent tuberculosis infection screening project. Samples within C50±20% are suspected to show relatively low reporducible results of high inversion between postivie and negative.
Enzyme-Linked Immunosorbent Assay ; Interferon-gamma Release Tests ; Interferons ; Latent Tuberculosis ; Mass Screening ; Methods ; Plasma

Cystic echinococcosis (CE) in sheep is a hazardous zoonotic parasitic disease that is caused by Echinococcus granulosus (Eg). At present, serological test is an important diagnostic method for Eg infection in domestic animals. Here, a fusion protein Eg mefAg-1 harboring 8 dominant B-cell epitopes of Eg such as antigen B, tetraspanin 1, tetraspanin 6, reticulon and Eg95 was produced in E. coli and evaluated for CE in sheep by indirect ELISA. Eg mefAg-1 showed in ELISA a high sensitivity (93.41%) and specificity (99.31%), with a coincidence rate of 97.02%. Overall, it is suggested that the Eg mefAg-1 could be a potential antigen candidate for CE serodiagnosis in sheep.
Animals, Domestic ; Echinococcosis ; Echinococcus granulosus ; Enzyme-Linked Immunosorbent Assay ; Epitopes, B-Lymphocyte ; Methods ; Parasitic Diseases ; Sensitivity and Specificity ; Serologic Tests ; Sheep

Trigonella foenum-graceum L. (fenugreek) is a phytoestrogen, a nonsteroidal organic chemical compound from plants which has similar mechanism of action to sex hormone estradiol-17β. This study aims to assess the effectivity of fenugreek seeds extract on collagen type I alpha 1 (COL1A1) and collagen type III alpha 1 (COL3A1) which are both decreased in aging skin and become worsen after menopause. This in vitro experimental study used old human dermal fibroblast from leftover tissue of blepharoplasty on a postmenopausal woman (old HDF). As a control of the fenugreek's ability to trigger collagen production, we used fibroblast from preputium (young HDF). Subsequent to fibroblast isolation and culture, toxicity test was conducted on both old and young HDF by measuring cell viability on fenugreek extract with the concentration of 5 mg/mL to 1.2 µg/mL which will be tested on both HDF to examine COL1A1 and COL3A1 using ELISA, compared to no treatment and 5 nM estradiol. Old HDF showed a 4 times slower proliferation compared to young HDF (p<0.05). Toxicity test revealed fenugreek concentration of 0.5 – 2 µg/mL was non-toxic to both old and young HDF. The most significant fenugreek concentration to increase COL1A1 and COL3A1 secretion was 2 µg/mL (p<0.05).
Aging ; Blepharoplasty ; Cell Survival ; Collagen Type I ; Collagen Type III ; Collagen ; Enzyme-Linked Immunosorbent Assay ; Estradiol ; Female ; Fibroblasts ; Humans ; In Vitro Techniques ; Menopause ; Phytoestrogens ; Skin ; Toxicity Tests ; Trigonella

OBJECTIVE: To investigate the methods for verifying and comparing performance of HIV testing methods and procedure analysis in blood station laboratories so as to meet the requirements of ISO15189 accreditation. METHODS: The performance of HIV test was verified by the automatic ELISA analyzer, the intra- and inter-assay precision was analyzed and evaluated by intra- and inter-assay repeat tests, the compliance rate was verified by the test results of the standard serum plate and the external quality assessment from the Ministry of Health in the past 2 years, the limit of detection was verified through continuous dilution of a known amount of reference serum for internal quality control, the status of the instrument was evaluated by testing one HIV-negative specimen, one HIV-negative with other positive markers, one strong HIV-positive specimen and two weak HIV-positive specimens. RESULTS: The intra- and inter-assay precisions were 5.12% and 16.81% respectively, the compliance rate of the serum plate test was 100%, the compliance of the external quality assessment results was 100%, the limits of detection for HIV was 1.42 NCU/ml, and the consistency of the detection systems was 100%. CONCLUSION The analytical performance of the HIV test methods and procedures accords with the requirements of the reagent instructions, the comparison of the test systems meets the verification requirements.
Enzyme-Linked Immunosorbent Assay ; HIV ; Mass Screening ; Quality Control ; Serologic Tests

BACKGROUND: Eosinophilia is well recognized in specific conditions. The objective of the present study was to determine clinico-radiologic characteristics of eosinophilia and changes in prevalence over 10 years in recipients of private health screening program at a tertiary hospital in Korea. METHODS: Data of private health screening program recipients at the health promotion center of Chung-Ang University Hospital from 2004 to 2013 were collected. Health-related questionnaires and laboratory findings of private health screening program with possible relation with eosinophilia were reviewed. Results of enzyme-linked immunosorbent assay (ELISA) for parasite, chest computed tomography, and pulmonary function test were also reviewed. RESULTS: The cumulative prevalence of eosinophilia was 4.0% (1,963 of 48,928). Prevalence of eosinophilia showed a decreased trend from 2004 to 2013. Most cases (96.6%) had mild degree of eosinophilia. Eosinophilic subjects were older and male-predominant. They showed lower levels of forced expiratory volume in 1 second (FEV₁%), forced vital capacity (FVC%), and FEV₁/FVC than those without eosinophilia. Eosinophilic subjects showed higher positive rate for common parasite in ELISA than those without eosinophilia. On radiologic findings, consolidation and ground glass opacities were positively associated with the degree of eosinophilia. When eosinophil was classified based on severity, statistically significant correlation between the severity of eosinophil and radiologic abnormalities was found. CONCLUSION: Eosinophilia is uncommon in healthy population. It usually occurs at a mild degree. Eosinophilic patients have more radiologic abnormalities compared to those without eosinophilia. Such radiologic abnormalities are associated with the severity of eosinophilia.
Enzyme-Linked Immunosorbent Assay ; Eosinophilia* ; Eosinophils ; Forced Expiratory Volume ; Glass ; Health Promotion ; Humans ; Korea ; Mass Screening* ; Parasites ; Prevalence ; Respiratory Function Tests ; Tertiary Care Centers ; Thorax ; Tomography, X-Ray Computed ; Vital Capacity

BACKGROUND/AIMS: To use serological and multiplex polymerase chain reaction (PCR) assays to examine sputum samples from patients experiencing acute exacerbation of chronic obstructive pulmonary disease (AECOPD) for the presence of atypical pathogens, including Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella pneumophila. METHODS: From September 2012 to February 2014, 341 patients with AECOPD attending outpatient clinics were enrolled as part of a randomized, double-blind, multicenter study. A commercial enzyme-linked immunosorbent assay was used to measure serum immunoglobulin M (IgM) and IgG antibody titers on the first day of the study and at 36 days post-enrollment. Multiplex PCR was used to test sputum samples for the presence of atypical pathogens. A urinary antigen test for L. pneumophila was performed on the first day. RESULTS: Nineteen patients (5.6%) showed serological evidence of acute infection with M. pneumoniae. Also, one and seven patients (2%) showed serological evidence of acute infection with C. pneumoniae and L. pneumophila, respectively. All DNA samples were negative for M. pneumoniae, C. pneumoniae, and L. pneumophila according to PCR. Only one urine sample was positive for L. pneumophila antigen, but serologic evidence was lacking. CONCLUSIONS: Serological testing suggested that infection by atypical pathogens during AECOPD was relatively uncommon. In addition, PCR provided no direct evidence of infection by atypical pathogens. Thus, atypical pathogens may not be a major cause of AECOPD in South Korea.
Ambulatory Care Facilities ; Chlamydophila pneumoniae ; DNA ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunoglobulin G ; Immunoglobulin M ; Korea ; Legionella pneumophila ; Multiplex Polymerase Chain Reaction ; Mycoplasma pneumoniae ; Pneumonia ; Pneumonia, Mycoplasma ; Polymerase Chain Reaction* ; Pulmonary Disease, Chronic Obstructive* ; Serologic Tests ; Sputum

Allergen immunotherapy (AIT) and diagnostic tests are based on well qualified allergen extracts, which are derived from biologic organisms. The allergenicity of the extracts is markedly affected by the climate, soil, year of production, storage methods, and manufacturing processes. Thus, standardization is a crucial process to guarantee the clinical efficacy and safety of the treatment and diagnostic reagents in allergic diseases. There are 2 different standardization processes, one is In vivo and the other is in vitro standardization. In vivo standardization is done by skin prick or intradermal tests. For in vitro standardization, measurements of weight/volume and protein nitrogen units have been widely used since the early period of AIT. In the 1970s, immunological methods such as radial immunodiffusion, enzyme-linked immunosorbent assay (ELISA) inhibition test and basophil activation test were developed. Allergen potency measured by ELISA inhibition test reflects the potency measured by skin tests and has been widely used for quality control of batch-to-batch variation. Recently, standardizations focused on the major allergen content of extracts have developed. Standardization for major allergens requires reliable reference materials (RMs) made of recombinant allergens and 2-site ELISA kits. However, only a few reliable RM and 2-site ELISA kits are available. For the standardization process, allergen RMs are essential. The Center for Biologics Evaluation and Research of the U.S. Food and Drug Administration provides 19 allergen RMs, and our research team also proved 9 RMs which are important in Korea. In conclusion, allergen standardization is an essential process for the development of reliable treatment and diagnostic reagents, and allergy specialist should be familiar with the concept of allergen standardization.
Allergens ; Basophils ; Biological Products ; Climate ; Desensitization, Immunologic ; Diagnostic Tests, Routine ; Enzyme-Linked Immunosorbent Assay ; Hypersensitivity ; Immunodiffusion ; In Vitro Techniques ; Indicators and Reagents ; Intradermal Tests ; Korea ; Nitrogen ; Quality Control ; Skin ; Skin Tests ; Soil ; Specialization ; Treatment Outcome ; United States Food and Drug Administration