Correlation of Automated Chemiluminescent Method with Enzyme-Linked Immunosorbent Assay (ELISA) Antibody Titers in Convalescent COVID-19 Plasma Samples: Development of Rapid, Cost-Effective Semi-Quantitative Diagnostic Methods

Until recently, the incidence of COVID-19 was primarily estimated using molecular diagnostic methods. However, the number of cases is vastly underreported using these methods. Seroprevalence studies estimate cumulative infection incidences and allow monitoring of transmission dynamics, and the presence of neutralizing antibodies in the population. In February 2020, the Mexican Social Security Institute began conducting anonymous unrelated sampling of residual sera from specimens across the country, excluding patients with fever within the previous two weeks and/or patients with an acute respiratory infection. Sampling was carried out weekly and began 17 days before Mexico’s first officially confirmed case. The 24,273 sera obtained were analyzed by chemiluminescent-linked immunosorbent assay (CLIA) IgG S1/S2 and, later, positive cases using this technique were also analyzed to determine the rate of neutralization using the enzyme-linked immunosorbent assay (ELISA). We identified 40 CLIA IgG positive cases before the first official report of SARS-CoV-2 infection in Mexico. The national seroprevalence was 3.5% in February and 33.5% in December. Neutralizing activity among IgG positives patients during overall study period was 86.1%. The extent of the SARS-CoV-2 infection in Mexico is 21 times higher than that reported by molecular techniques. Although the general population is still far from achieving herd immunity, epidemiological indicators should be re-estimated based on serological studies of this type.

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Plasma checkpoint protein 1 (Chk1) as a potential diagnostic biomarker for opisthorchiasis and cholangiocarcinoma

Cancer Biomarkers ◽

10.3233/cbm-210170 ◽

2021 ◽

pp. 1-13

Author(s):

Teva Phanaksri ◽

Yodying Yingchutrakul ◽

Sittiruk Roytrakul ◽

Sattrachai Prasopdee ◽

Anthicha Kunjantarachot ◽

...

Keyword(s):

Diagnostic Methods ◽

Protein Network ◽

Enzyme Linked Immunosorbent Assay ◽

Plasma Samples ◽

Diagnostic Biomarker ◽

Checkpoint Protein ◽

Venn Diagrams ◽

Network Prediction ◽

Candidate Protein ◽

Potential Biomarkers

BACKGROUND: Patients infected with a parasite often develop opisthorchiasis viverrini, which often progresses into cholangiocarcinoma (CCA) due to the asymptomatic nature of the infection. Currently, there are no effective diagnostic methods for opisthorchiasis or cholangiocarcinoma. OBJECTIVE: The aim of this study was to identify the host-responsive protein that can be developed as a diagnostic biomarker of opisthorchiasis and cholangiocarcinoma. METHODS: Plasma samples were collected from non-OVCCA, OV, and CCA subjects, and the proteomes were investigated by LC-MS/MS. Venn diagrams and protein network prediction by STITCH were used to identify the potential biomarkers. The level of candidate protein, the plasma checkpoint protein 1 (Chk1), was measured by indirect enzyme-linked immunosorbent assay (ELISA). RESULTS: Chk1 was present in the center of the protein network analysis in both the OV and CCA groups. In addition, the plasma Chk1 levels were significantly increased in both groups (P< 0.05). The sensitivity of the opisthorchiasis viverrini and cholangiocarcinoma was 59.38% and 65.62%, respectively, while the specificity of both was 85.71%. CONCLUSION: Chk1 was identified by differential plasma proteomes and was increased in O. viverrini-infected and cholangiocarcinoma-derived plasma samples. Higher levels of plasma Chk1 levels may serve as a potential diagnostic biomarker for opisthorchiasis and cholangiocarcinoma.

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Comparison of an enzyme-linked immunosorbent assay for quantitation of rotavirus antibodies with complement fixation in an epidemiological survey

Journal of Clinical Microbiology ◽

10.1128/jcm.8.3.268-276.1978 ◽

1978 ◽

Vol 8 (3) ◽

pp. 268-276

Author(s):

L H Ghose ◽

R D Schnagl ◽

I H Holmes

Keyword(s):

Immunosorbent Assay ◽

Complement Fixation ◽

Age Groups ◽

Enzyme Reaction ◽

Epidemiological Survey ◽

Enzyme Linked Immunosorbent Assay ◽

Marker Enzyme ◽

Aminosalicylic Acid ◽

Antibody Titers ◽

Antibody Levels

The development of a micro-scale enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase as the marker enzyme for the detection and measurement of human rotavirus antibodies is described. A semipurified preparation of the serologically related simian agent, SA-11 virus, was used as the antigen. Test sera were reacted with antigen-sensitized wells in disposable poly-vinyl microplates. Any attached antibody was detected by the addition of peroxidase-labeled anti-species immunoglobulin (conjugate) followed by assay of the enzyme reaction with its substrate, hydrogen peroxide plus 5-aminosalicylic acid. This micro-ELISA was compared with complement fixation in a seroepidemiological study of the age prevalence of rotavirus antibody in Aboriginal and European populations living in the same outback area in Australia. The ELISA (results read with the naked eye) proved to be approximately 16 times more sensitive than complement fixation. Of Aborigines, 71% had rotavirus complement-fixing antibody, as compared to 45% of Europeans. By ELISA 100% of both populations had rotavirus antibodies. Mean antibody titers in the different age groups were higher in Aborigines than in Europeans. Antibody levels rose steeply throughout the first 20 years of life, remained high during the next 20 years, then increased again at least up to the age of 60 years. The micro-ELISA was practical, simple to perform, and more suitable than complement fixation for large seroepidemiological rotavirus studies. It also has potential for serodiagnosis of the disease, both in the laboratory and in the field.

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Paraneoplastic pemphigus: A trait d’union between dermatology and oncology

Advances in Modern Oncology Research ◽

10.18282/amor.v1.i2.42 ◽

2015 ◽

Vol 1 (2) ◽

Cited By ~ 2

Author(s):

Dario Didona ◽

Biagio Didona ◽

Antonio G Richetta ◽

Carmen Cantisani ◽

Elisa Moliterni ◽

...

Keyword(s):

Autoimmune Disease ◽

Clinical Features ◽

Immunosorbent Assay ◽

Indirect Immunofluorescence ◽

Laboratory Tests ◽

Diagnostic Methods ◽

Enzyme Linked Immunosorbent Assay ◽

Paraneoplastic Pemphigus ◽

Pathological Evaluation

<p style="margin: 0cm 0cm 8pt; text-align: justify; line-height: 150%;">Paraneoplastic pemphigus is a rare autoimmune disease of the skin associated with neoplasm. Nowadays, the pathogenesis of paraneoplastic pemphigus is not fully understood. Due to its rarity, various criteria have been proposed for the diagnosis. For this reason, several diagnostic methods have been considered useful for the diagnosis of paraneoplastic pemphigus including indirect immunofluorescence, direct immune of fluorescence, immunoprecipitation, immunoblotting, and enzyme-linked immunosorbent assay (ELISA). However, the polymorphic clinical features and the various results of laboratory tests and pathological evaluation present a challenge for the clinicians.</p>

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Effect of Early Immunization on Antibody Response to Reimmunization with Measles Vaccine as Demonstrated by Enzyme-Linked Immunosorbent Assay (ELISA)

PEDIATRICS ◽

10.1542/peds.74.1.90 ◽

1984 ◽

Vol 74 (1) ◽

pp. 90-93

Author(s):

M. Dianne Murphy ◽

Philip A. Brunell ◽

Alan W. Lievens ◽

Ziad M. Shehab

Keyword(s):

Antibody Response ◽

Immunosorbent Assay ◽

San Antonio ◽

Significant Risk ◽

Enzyme Linked Immunosorbent Assay ◽

Measles Vaccine ◽

Young Infants ◽

Antibody Titers

A measles epidemic in San Antonio, Texas provided a population of children who were immunized at ≤10 months of age and reimmunized at ≥15 months of age. Of these children, 302 were evaluated for measles antibody by the sensitive enzyme-linked immunosorbent assay (ELISA), and their responses were compared with those of 300 children who had been immunized at the customary time (≥15 months) with a single immunization. There were only five seronegative findings in each group. The children immunized at the customary time did have significantly higher (P < .001) antibody titers than the children immunized at ≤10 months and reimmunized at ≥15 months. These results indicate that early immunization followed by reimmunization may be indicated when young infants are at significant risk of measles exposure. This approach should not create an increased number of serologically nonresponsive children when reimmunized at ≥15 months.

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Outlooks of synthetic mycobacterial antigens in serological diagnostics of leprosy

Infekcionnye bolezni ◽

10.20953/1729-9225-2020-4-164-168 ◽

2020 ◽

Vol 18 (4) ◽

pp. 164-168

Author(s):

A.G. Korolyova-Ushakova ◽

◽

E.V. Baranova ◽

S.G. Ignatov ◽

P.V. Solov’ev ◽

...

Keyword(s):

Immunosorbent Assay ◽

Biopsy Specimen ◽

Histological Study ◽

Mycobacterium Leprae ◽

Diagnostic Methods ◽

Enzyme Linked Immunosorbent Assay ◽

Standard Methods ◽

Skin Biopsy Specimen ◽

Mycobacterial Antigens ◽

Serological Diagnostics

Despite the fact that the incidence of leprosy in Russia is sporadic, the number of newly identified patients has increased in recent years. In 2017–2018, 4 new cases of leprosy were registered in Russia. The standard methods of research for diagnosis, in addition to the clinical picture, are bacterioscopic study of the skin scarificates and histological study of the skin biopsy specimen. Currently, additional methods are being developed and used to confirm the diagnosis of leprosy, namely, modern serological and genetic diagnostic methods. To use methods such as enzyme-linked immunosorbent assay (ELISA) and membrane immunochromatographic analysis (leprosy LF serotest), it is appropriate to use domestic synthetic mycobacterial antigens (SMA). Key words: Mycobacterium leprae, leprosy, synthetic mycobacterial antigens, PGL-1(phenolic glycolipid-1), LAM (lipoarabinomannan), serodiagnostics, enzyme-linked immunosorbent assay (ELISA), lateral flow (LF) test, BSA (bovine serum albumin)

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Autoimmune antibodies correlate with immune checkpoint therapy-induced toxicities

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1908079116 ◽

2019 ◽

Vol 116 (44) ◽

pp. 22246-22251 ◽

Cited By ~ 22

Author(s):

Salahaldin A. Tahir ◽

Jianjun Gao ◽

Yuji Miura ◽

Jorge Blando ◽

Rebecca S. S. Tidwell ◽

...

Keyword(s):

Adverse Events ◽

Cancer Patients ◽

Immunosorbent Assay ◽

Immune Checkpoint ◽

Additional Patient ◽

Enzyme Linked Immunosorbent Assay ◽

Plasma Samples ◽

Serological Analysis ◽

Autoimmune Antibodies ◽

Expression Libraries

Immune checkpoint (IC) therapy provides substantial benefits to cancer patients but can also cause distinctive toxicities termed immune-related adverse events (irAEs). Biomarkers to predict toxicities will be necessary to improve management of patients receiving IC therapy. We relied on serological analysis of recombinant cDNA expression libraries to evaluate plasma samples from patients treated with IC therapy and identified autoantibodies, both in pretreatment and on-treatment samples prior to the development of irAEs, which correlate with the development of immune-related hypophysitis (anti-GNAL and anti-ITM2B autoantibodies) and pneumonitis (anti-CD74 autoantibody). We developed an enzyme-linked immunosorbent assay and tested additional patient samples to confirm our initial findings. Collectively, our data suggest that autoantibodies may correlate with irAEs related to IC therapy, and specific autoantibodies may be detected early for the management of irAEs.

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An enzyme-linked immunosorbent assay for the detection of Rathayibacter toxicus, the bacterium involved in annual ryegrass toxicity, in hay

Australian Journal of Agricultural Research ◽

10.1071/ar03125 ◽

2006 ◽

Vol 57 (7) ◽

pp. 731 ◽

Cited By ~ 6

Author(s):

A. M. Masters ◽

A. R. Gregory ◽

R. J. Evans ◽

J. E. Speijers ◽

S. S. Sutherland

Keyword(s):

Monoclonal Antibody ◽

Immunosorbent Assay ◽

Specific Antigen ◽

Cost Effective ◽

Enzyme Linked Immunosorbent Assay ◽

Annual Ryegrass ◽

Capture Assay ◽

Large Numbers ◽

Soluble Polysaccharide ◽

Annual Ryegrass Toxicity

An enzyme-linked immunosorbent assay (ELISA) for Rathayibacter toxicus is described. The development of a monoclonal antibody for a specific antigen from R. toxicus and a polyclonal antibody raised against the same R. toxicus preparation enabled a capture assay format. The assay is specific for a soluble polysaccharide produced by the bacterium and was found to be sensitive enough to detect antigen equivalent to less than one gall per kilogram of hay. The applicability of the assay to samples of pasture or hay is demonstrated. Cost-effective testing of large numbers of samples for the presence of R. toxicus is possible with the ELISA. This will assist stockowners, hay producers, and hay exporters in the management of the risk of annual ryegrass toxicity.

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Pneumococcal Type 22F Polysaccharide Absorption Improves the Specificity of a Pneumococcal-Polysaccharide Enzyme-Linked Immunosorbent Assay

Clinical and Diagnostic Laboratory Immunology ◽

10.1128/cdli.8.2.266-272.2001 ◽

2001 ◽

Vol 8 (2) ◽

pp. 266-272 ◽

Cited By ~ 210

Author(s):

Nelydia F. Concepcion ◽

Carl E. Frasch

Keyword(s):

Correlation Coefficient ◽

Immunosorbent Assay ◽

Pneumococcal Vaccination ◽

Correlation Coefficients ◽

Enzyme Linked Immunosorbent Assay ◽

Igg Antibody ◽

Functional Activities ◽

Antibody Titers ◽

The Common ◽

Elisa Inhibition

ABSTRACT The specificity of the immune response to the 23-valent pneumococcal-polysaccharide (PS) vaccine in healthy adults and to a pneumococcal conjugate vaccine in infants was examined by measuring immunoglobulin G (IgG) antibody titers by enzyme-linked immunosorbent assay (ELISA) and the opsonophagocytosis assay. ELISA measures total antipneumococcal IgG titers including the titers of functional and nonfunctional antibodies, while the opsonophagocytosis assay measures only functional-antibody titers. Twenty-four pairs of pre- and post-pneumococcal vaccination sera from adults were evaluated (ELISA) for levels of IgG antibodies against serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F. Twelve of the pairs were also examined (opsonophagocytosis assay) for their functional activities. The correlation coefficients between assay results for most types ranged from 0.75 to 0.90, but the correlation coefficient was only about 0.6 for serotypes 4 and 19F. The specificities of these antibodies were further examined by the use of competitive ELISA inhibition. A number of heterologous polysaccharides (types 11A, 12F, 15B, 22F, and 33A) were used as inhibitors. Most of the sera tested showed cross-reacting antibodies, in addition to those removed by pneumococcal C PS absorption. Our data suggest the presence of a common epitope that is found on most pneumococcal PS but that is not absorbed by purified C PS. Use of a heterologous pneumococcal PS (22F) to adsorb the antibodies to the common epitope increased the correlation between the IgG ELISA results and the opsonophagocytosis assay results. The correlation coefficient improve from 0.66 to 0.92 for type 4 and from 0.63 to 0.80 for type 19F. These common-epitope antibodies were largely absent in infants at 7 months of age, suggesting the carbohydrate nature of the epitope.

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