Antibody Testing: Analysis of the Specificity of Antibody Detection in a Non-Diisocyanate-Exposed Population

The aim of the present study was to evaluate the possible utilization of saliva and urine as alternative samples to serum for the diagnosis of human immunodeficiency virus (HIV) infection. A total of 302 individuals participated in the study: 187 HIV-infected individuals (106 had Centers for Disease Control and Prevention [CDC] stage II infection, 19 had CDC stage III infection, and 62 had CDC stage IV infection) and 115 noninfected persons (46 of the noninfected persons were blood donors and 69 belonged to a group at high risk of HIV infection). Paired saliva and urine samples were taken from each of the participants in the study. The presence of HIV-specific antibodies was detected by an enzyme-linked fluorescent assay (ELFA), and the result was confirmed by Western blot analysis (WB). The ELFA with saliva gave maximum sensitivity and specificity values, while ELFA had lower sensitivity (95.2%) and specificity (97.4%) values for detection of HIV antibody in urine samples. WB with all saliva samples fulfilled the World Health Organization criterion for positivity, while only 96.8% of the urine samples were confirmed to be positive by WB. Among the four reactivity patterns found by WB of these alternative samples, the most frequent included bands against three groups of HIV structural proteins (was ENV, POL, and GAG). The reactivity bands most frequently observed were those for the proteins gp160 and gp120. The least common reactivity band was the band for protein p17. The detection of HIV antibodies in saliva samples by means of ELFA with the possibility of later confirmation by WB makes saliva an alternative to serum for possible use in the diagnosis of infection. In contrast, HIV antibody detection in urine samples by the same methodology (ELFA) could be taken into consideration for use in epidemiological studies.

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Chikungunya Virus RNA and Antibody Testing at a National Reference Laboratory since the Emergence of Chikungunya Virus in the Americas

Clinical and Vaccine Immunology ◽

10.1128/cvi.00720-14 ◽

2014 ◽

Vol 22 (3) ◽

pp. 291-297 ◽

Cited By ~ 23

Author(s):

Harry E. Prince ◽

Brent L. Seaton ◽

Jose L. Matud ◽

Hollis J. Batterman

Keyword(s):

Chikungunya Virus ◽

Large Data ◽

Nucleic Acid Amplification ◽

Antibody Detection ◽

Reference Laboratory ◽

Antibody Testing ◽

Data Set ◽

Rna Detection ◽

Antibody Titers ◽

The Relationship

ABSTRACTSince first reported in the Americas in December 2013, chikungunya virus (CHIKV) infections have been documented in travelers returning from the Caribbean, with many cases identified by CHIKV antibody and/or RNA testing at our laboratory. We used our large data set to characterize the relationship between antibody titers and RNA detection and to estimate IgM persistence. CHIKV RNA was measured by nucleic acid amplification and CHIKV IgG/IgM by indirect immunofluorescence. Of the 1,306 samples submitted for RNA testing in January through September 2014, 393 (30%) were positive; for 166 RNA-positive samples, CHIKV antibody testing was also ordered, and 84% were antibody negative. Of the 6,971 sera submitted for antibody testing in January through September 2014, 1,811 (26%) were IgM positive; 1,461 IgM positives (81%) were also IgG positive. The relationship between the CHIKV antibody titers and RNA detection was evaluated using 376 IgM-positive samples (138 with RNA testing ordered and 238 deidentified and tested for RNA). RNA detection showed no significant association with the IgM titer but was inversely related to the IgG titer; 63% of the IgG negative sera were RNA positive, compared to 36% of sera with low IgG titers (1:10 to 1:80) and 16% with IgG titers of ≥1:160. Using second-sample results from 62 seroconverters, we estimated that CHIKV IgM persists for 110 days (95% confidence interval, 78 to 150 days) after the initial antibody-negative sample. These findings indicate that (i) RNA detection is more sensitive than antibody detection early in CHIKV infection, (ii) in the absence of RNA results, the IgG titer of the IgM-positive samples may be a useful surrogate for viremia, and (iii) CHIKV IgM persists for approximately 4 months after symptom onset.

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An evaluation of the performance of OraQuick® ADVANCE Rapid HIV-1/2 Test in a high-risk population attending genitourinary medicine clinics in East London, UK

International Journal of STD & AIDS ◽

10.1258/ijsa.2008.008132 ◽

2008 ◽

Vol 19 (10) ◽

pp. 665-667 ◽

Cited By ~ 17

Author(s):

J Zelin ◽

N Garrett ◽

J Saunders ◽

F Warburton ◽

J Anderson ◽

...

Keyword(s):

High Risk ◽

Test Performance ◽

Predictive Value ◽

Risk Groups ◽

Antibody Detection ◽

High Risk Population ◽

Antibody Testing ◽

Observer Error ◽

The Uk ◽

Hiv 1

To date, no data have been published on the use of OraQuick® ADVANCE Rapid HIV-1/2 Test (OraQuick) in the UK. We report preliminary findings of an ongoing evaluation of OraQuick in UK genitourinary (GU) medicine clinics. A total of 820 samples from patients in high-risk groups for HIV were tested with OraQuick and results were compared with standard HIV antibody testing. HIV prevalence (enzyme immunoassay [EIA]) was 5.73%, sensitivity of OraQuick was 93.64% (95% CI 82.46–98.66%), specificity 99.87% (99.28–100%), positive predictive value 97.78% (88.27–99.94%) and negative predictive value 99.61% (98.87–99.92%). This includes three false-negatives considered to be due to observer error and now rectified by further training. This has increased test sensitivity to 100%. Our observed test performance of OraQuick compares well with EIA and with other rapid tests. We believe that simple, non-invasive antibody detection tests such as OraQuick can increase HIV testing and diagnosis in UK GU medicine and community settings.

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Antibody testing for COVID-19: A report from the National COVID Scientific Advisory Panel

Wellcome Open Research ◽

10.12688/wellcomeopenres.15927.1 ◽

2020 ◽

Vol 5 ◽

pp. 139 ◽

Cited By ~ 33

Author(s):

Emily R. Adams ◽

Mark Ainsworth ◽

Rekha Anand ◽

Monique I. Andersson ◽

Kathryn Auckland ◽

...

Keyword(s):

Symptom Onset ◽

Vaccine Development ◽

Detection Threshold ◽

Negative Control ◽

Antibody Detection ◽

Advisory Panel ◽

Antibody Testing ◽

Highly Sensitive ◽

History Of ◽

The Uk

Background: The COVID-19 pandemic caused >1 million infections during January-March 2020. There is an urgent need for reliable antibody detection approaches to support diagnosis, vaccine development, safe release of individuals from quarantine, and population lock-down exit strategies. We set out to evaluate the performance of ELISA and lateral flow immunoassay (LFIA) devices. Methods: We tested plasma for COVID (severe acute respiratory syndrome coronavirus 2; SARS-CoV-2) IgM and IgG antibodies by ELISA and using nine different LFIA devices. We used a panel of plasma samples from individuals who have had confirmed COVID infection based on a PCR result (n=40), and pre-pandemic negative control samples banked in the UK prior to December-2019 (n=142). Results: ELISA detected IgM or IgG in 34/40 individuals with a confirmed history of COVID infection (sensitivity 85%, 95%CI 70-94%), vs. 0/50 pre-pandemic controls (specificity 100% [95%CI 93-100%]). IgG levels were detected in 31/31 COVID-positive individuals tested ≥10 days after symptom onset (sensitivity 100%, 95%CI 89-100%). IgG titres rose during the 3 weeks post symptom onset and began to fall by 8 weeks, but remained above the detection threshold. Point estimates for the sensitivity of LFIA devices ranged from 55-70% versus RT-PCR and 65-85% versus ELISA, with specificity 95-100% and 93-100% respectively. Within the limits of the study size, the performance of most LFIA devices was similar. Conclusions: Currently available commercial LFIA devices do not perform sufficiently well for individual patient applications. However, ELISA can be calibrated to be specific for detecting and quantifying SARS-CoV-2 IgM and IgG and is highly sensitive for IgG from 10 days following first symptoms.

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Antibody testing for COVID-19: A report from the National COVID Scientific Advisory Panel

10.1101/2020.04.15.20066407 ◽

2020 ◽

Cited By ~ 36

Author(s):

◽

Emily R Adams ◽

Mark Ainsworth ◽

Rekha Anand ◽

Monique I Andersson ◽

...

Keyword(s):

Symptom Onset ◽

Vaccine Development ◽

Detection Threshold ◽

Negative Control ◽

Antibody Detection ◽

Advisory Panel ◽

Antibody Testing ◽

Highly Sensitive ◽

History Of ◽

The Uk

ABSTRACTBackgroundThe COVID-19 pandemic caused >1 million infections during January-March 2020. There is an urgent need for reliable antibody detection approaches to support diagnosis, vaccine development, safe release of individuals from quarantine, and population lock-down exit strategies. We set out to evaluate the performance of ELISA and lateral flow immunoassay (LFIA) devices.MethodsWe tested plasma for COVID (SARS-CoV-2) IgM and IgG antibodies by ELISA and using nine different LFIA devices. We used a panel of plasma samples from individuals who have had confirmed COVID infection based on a PCR result (n=40), and pre-pandemic negative control samples banked in the UK prior to December-2019 (n=142).ResultsELISA detected IgM or IgG in 34/40 individuals with a confirmed history of COVID infection (sensitivity 85%, 95%CI 70-94%), vs. 0/50 pre-pandemic controls (specificity 100% [95%CI 93-100%]). IgG levels were detected in 31/31 COVID-positive individuals tested ≥10 days after symptom onset (sensitivity 100%, 95%CI 89-100%). IgG titres rose during the 3 weeks post symptom onset and began to fall by 8 weeks, but remained above the detection threshold. Point estimates for the sensitivity of LFIA devices ranged from 55-70% versus RT-PCR and 65-85% versus ELISA, with specificity 95-100% and 93-100% respectively. Within the limits of the study size, the performance of most LFIA devices was similar.ConclusionsCurrently available commercial LFIA devices do not perform sufficiently well for individual patient applications. However, ELISA can be calibrated to be specific for detecting and quantifying SARS-CoV-2 IgM and IgG and is highly sensitive for IgG from 10 days following first symptoms.

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263. Advances in Diagnosis of Progressive Coccidioidomycos: Experience in 164 Cases and 508 Controls

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.338 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S146-S146

Author(s):

Robert Myers ◽

Holbrook Eric ◽

Lawrence J Wheat ◽

Christelle Kassis ◽

Michelle Durkin

Keyword(s):

Retrospective Study ◽

Sensitivity And Specificity ◽

Advanced Disease ◽

Turnaround Time ◽

Antibody Detection ◽

Immunocompromised Patients ◽

Antibody Testing ◽

Main Method ◽

Antigen Testing ◽

Urine And Serum

Abstract Background Antibody detection is the main method for diagnosis of coccidioidomycosis but has limitations including sensitivity and turnaround time. The MVISTA Coccidioides antigen enzyme immunoassay (EIA) is recommended for testing CSF in suspected Coccidioides meningitis. The early reports on urine and serum antigen testing evaluated small numbers of patients who were mostly immunocompromised with advanced disease. Methods A retrospective study, including all patients in whom Coccidioides antigen testing was performed between January 2013 and May 2017, was conducted at Maricopa Integrated Health System (MIHS). Sensitivity and specificity of antigen testing at MiraVista Diagnostics and antibody testing at MIHS or commercial laboratories were evaluated in 164 cases and 508 controls. Results The sensitivity of antigen testing was 51% and specificity was 99%. The sensitivity of antigen detection was highest if both urine and serum were tested (57%) than if only urine was tested (38%). The sensitivity of antibody testing was 84% and the specificity was 94% by immunodiffusion (ID). The sensitivity and specificity of antigen or ID antibody testing both were 94%. Sensitivity of antigen testing was 57% in proven and 58% in probable cases, ID antibody in 85% of proven and 75% of probable and antigen or ID antibody in 93% of proven and 95% of probable cases. Antigen was detected more often in disseminated (79%) than pulmonary cases (42%) as was ID antibody, 91% and 79%, respectively. Antigen testing was more sensitive in immunocompromised (76%) than non-immunocompromised patients (41%) while ID antibody was less sensitive in immunocompromised (74%) than in non-immunocompromised patients (93%). Combined antigen and ID antibody testing provided the highest sensitivity, 94% in all cases, 94% in immunocompromised and 95% in non-immunocompromised patients. Conclusion These findings support testing urine and serum for Coccidioides antigen and serum for ID antibodies for diagnosis of progressive pulmonary or disseminated coccidioidomycosis. Disclosures All authors: No reported disclosures.

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The utility of Coccidioides antigen and antibody detection in cerebrospinal fluid in the diagnosis of canine central nervous system coccidioidomycosis

American Journal of Veterinary Research ◽

10.2460/ajvr.21.08.0121 ◽

2022 ◽

pp. 1-5

Author(s):

Christine D. Butkiewicz ◽

Cody J. Alcott ◽

Janelle Renschler ◽

Lawrence J. Wheat ◽

Lisa F. Shubitz

Keyword(s):

Clinical Signs ◽

High Specificity ◽

Antibody Detection ◽

Antibody Testing ◽

Endemic Region ◽

Predictive Values ◽

Csf Analysis ◽

Neurologic Disorders ◽

Low Sensitivity ◽

A Prospective Study

Abstract OBJECTIVE To evaluate the utility of enzyme immunoassays (EIAs) for the detection of Coccidioides antigen and antibody in CSF in the diagnosis of CNS coccidioidomycosis in dogs. ANIMALS 51 dogs evaluated for CNS disease in a single specialty center in Tucson in 2016. PROCEDURES Excess CSF after routine analysis was banked after collection from dogs presented to the neurology service. Samples were tested by EIA for presence of Coccidioides antigen and antibody. Clinical data were collected from medical records retrospectively. RESULTS 22 dogs were diagnosed with CNS coccidioidomycosis (CCM) or another neurologic disease (non-CCM). These groups of dogs overlapped in the presenting complaints, MRI results, and routine CSF analysis results. Four dogs, all with CCM, had positive antigen EIA results. With clinical diagnosis used as the reference standard, CSF antigen testing had low sensitivity (20%) but high specificity (100%) for diagnosis of CCM. Ten dogs with CCM and 4 dogs with other diagnoses had antibody detected in CSF by EIA. Sensitivity of CSF antibody testing was 46%, specificity was 86%, and positive and negative predictive values for the study population were 71% and 68%, respectively. Clinical Relevance Diagnosis of CNS coccidioidomycosis in dogs in an endemic region was hampered by overlap of clinical signs with other neurologic disorders and the low sensitivity of confirmatory diagnostics. The evaluated Coccidioides-specific EIAs performed on CSF can aid in the diagnosis. A prospective study is warranted to corroborate and refine these preliminary findings

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Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Prevalence in Blood in a Large School Community Subject to a Coronavirus Disease 2019 Outbreak: A Cross-sectional Study

Clinical Infectious Diseases ◽

10.1093/cid/ciaa955 ◽

2020 ◽

Cited By ~ 8

Author(s):

Juan Pablo Torres ◽

Cecilia Piñera ◽

Verónica De La Maza ◽

Anne J Lagomarcino ◽

Daniela Simian ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

School Community ◽

Antibody Detection ◽

Lower Grade ◽

Rt Pcr ◽

Antibody Testing ◽

Cross Sectional ◽

Large School ◽

First Case ◽

Antibody Positivity

Abstract Background A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak affecting 52 people from a large school community in Santiago, Chile, was identified (12 March) 9 days after the first case in the country. We assessed the magnitude of the outbreak and the role students and staff played using self-administered antibody detection tests and a self-administered survey. Methods The school was closed on 13 March, and the entire community was placed under quarantine. We implemented a home-delivery, self-administered, immunoglobin (Ig) G/IgM antibody test and survey to a classroom-stratified sample of students and all staff from 4–19 May. We aimed to determine the overall seroprevalence rates by age group, reported symptoms, and contact exposure, and to explore the dynamics of transmission. Results The antibody positivity rates were 9.9% (95% confidence interval [CI], 8.2–11.8) for 1009 students and 16.6% (95% CI, 12.1–21.9) for 235 staff. Among students, positivity was associated with a younger age (P = .01), a lower grade level (P = .05), prior real-time polymerase chain reaction (RT-PCR) positivity (P = .03), and a history of contact with a confirmed case (P < .001). Among staff, positivity was higher in teachers (P = .01) and in those previously RT-PCR positive (P < .001). Excluding RT-PCR–positive individuals, antibody positivity was associated with fever in adults and children (P = .02 and P = .002, respectively), abdominal pain in children (P = .001), and chest pain in adults (P = .02). Within antibody-positive individuals, 40% of students and 18% of staff reported no symptoms (P = .01). Conclusions Teachers were more affected during the outbreak and younger children were at a higher risk for infection, likely because index case(s) were teachers and/or parents from the preschool. Self-administered antibody testing, supervised remotely, proved to be a suitable and rapid tool. Our study provides useful information for school reopenings.

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Erytra Blood Group Analyser and Kode Technology testing of SARS-CoV-2 antibodies among convalescent patients and vaccinated individuals

10.1101/2021.08.26.21262219 ◽

2021 ◽

Author(s):

Christof Weinstock ◽

Willy A Flegel ◽

Kshitij Srivastava ◽

Sabine Kaiser ◽

Hubert Schrezenmeier ◽

...

Keyword(s):

Blood Group ◽

Antibody Formation ◽

Large Scale ◽

Red Cells ◽

Spike Protein ◽

Antibody Detection ◽

Short Peptides ◽

Population Surveys ◽

Antibody Testing ◽

Agglutination Assay

SummarySurveillance of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic requires tests to monitor antibody formation and prevalence. We detected SARS-CoV-2 antibodies using red cells coated by Kode technology with short peptides derived from the SARS-CoV-2 spike protein. Such modified red cells, called C19-kodecytes, can be used as reagent cells in any manual or automated column agglutination assay. We investigated the presence of SARS-CoV-2 antibodies in 130 samples from COVID-19 convalescent plasma donors using standard manual technique, two FDA authorized ELISA assays and a virus neutralisation assay. The sensitivity of the C19-kodecyte assay was 88%, comparable to the anti-SP and anti-NCP ELISAs (86% and 83%) and the virus neutralisation assay (88%). The specificity of the C19-kodecyte assay was 90% (anti-SP 100% and anti-NCP 97%). Likewise, 231 samples from 73 vaccinated individuals were tested with an automated analyser and we monitored the appearance and persistence of SARS-CoV-2 antibodies. The C19-kodecyte assay is a robust tool for SARS-CoV-2 antibody detection. Automated blood group analyser use enables large-scale SARS-CoV-2 antibody testing for vaccination monitoring in population surveys.

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Successful Anti-SARS-CoV-2 Spike Protein Antibody Response to Vaccination in MAGT1 Deficiency

Allergy & Rhinology ◽

10.1177/21526567211056239 ◽

2021 ◽

Vol 12 ◽

pp. 215265672110562

Author(s):

Maaz Jalil ◽

Marija Rowane ◽

Jayanth Rajan ◽

Robert Hostoffer

Keyword(s):

Antibody Response ◽

Messenger Rna ◽

Neutralizing Antibodies ◽

Office Visit ◽

Spike Protein ◽

Antibody Detection ◽

Epstein Barr Virus Infection ◽

Protein Antigens ◽

Antibody Testing ◽

Post Vaccination

Background Novel messenger RNA vaccines against severe acute respiratory syndrome coronavirus (SARS-CoV-2) have been vital in resolving the coronavirus disease-2019 (COVID-19) pandemic. Detection of neutralizing antibodies (NAbs) against the SARS-CoV-2 spike protein (S) confirms immunogenicity with high sensitivity and specificity. Few recent studies with primary and secondary immunodeficient cohorts present adequate or reduced antibody response. We describe the first reported successful response to anti-SARS-CoV-2 S antibody post-vaccination in magnesium transporter 1 (MAGT1) gene deficiency, more commonly recognized as x-linked immunodeficiency with magnesium defect, Epstein-Barr Virus infection, and neoplasia (XMEN). Case Presentation We present a 30-year-old male with selective anti-polysaccharide antibody deficiency, peripheral blood CD5 + /CD19 + B-cell predominance (97%), MAGT1 mutation, and reduced CD16 + CD56 + natural killer- and/or CD8 + T-cell receptor, Group 2, Member D expression. His initial immunological evaluation revealed all seronegative post-vaccination antibody titers but clinically adequate response to protein antigens tetanus and diphtheria anti-toxoids. COVID-19 vaccination and associated serology antibody testing was recommended at this office visit. Anti-SARS-CoV-2 immunoglobulin (Ig)M and IgG antibodies before and after the first BNT162b2 mRNA COVID-19 vaccine doses, as well as nucleocapsid antibody, were negative. S protein total antibody was reactive after the second dose. Discussion Robust immunological sequelae post-COVID-19 vaccination in the general population are well-documented in the recent literature. Few studies have evaluated COVID-19 vaccination antibody response in immunodeficient patients. The majority positive anti-S antibody detection in most primary immunodeficient (PID) patients among the few studies in the literature, such as the present case, support the safety and efficacy of mRNA COVID-19 vaccination in immunodeficient patients, although larger scale studies are needed. Conclusion We demonstrate successful vaccination in the PID MAGT1 deficiency in this first reported case of reactive anti-S antibody post-COVID-19 vaccination.

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