Name: COVID-19 Seroprevalence Test for IgG Antibody Levels Among Healthy Donors Across Different Pandemic Phases in Jeddah (Video) | JoVE Journal
Uploaded: 2025-06-24T14:00:00.000+00:00
Duration: 4 min 43 s
Description: Discover COVID-19 IgG seroprevalence patterns among healthy Jeddah donors across pre-lockdown, during-lockdown, and post-lockdown phases using ELISA and PCR methods. This study reveals 4.5% antibody positivity with significant post-lockdown increases.

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5 minutes

This Project was funded by the Deanship of Scientific Research (DSR) at King Abdulaziz University, Jeddah, under grant no. (G: 521-142-1441). The authors, therefore, acknowledge with thanks DSR for technical and financial support.

This research was approved by the Research Ethics Committee (REC) of the Unit of Biomedical Ethics at the Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia (Ref. No. 219-24). Informed consent was obtained from all participants for this study.
1. Study design
NOTE: A cross-sectional study at the Special Infectious Agents Unit (SIAU), King Fahd Medical Research Center (KFMRC), Jeddah, Saudi Arabia, to analyze COVID-19 prevalence in voluntary blood donors (BDs) from December 2019 to December 2020 was conducted.
<ol>
	<li>For an overview of the study design, highlighting the pandemic phases, participant recruitment, and the data collection and analysis methodology, see Figure 1.</li>
	<li>Use a serological immunoassay to detect anti-SARS-CoV-2 IgG antibodies, adhering to institutional ethical guidelines.</li>
</ol>
2. Sample collection
<ol>
	<li>Use the following inclusion criteria: Healthy adults aged 18-60 years; Willingness to provide informed consent for participation in the study; No history of SARS-CoV-2 infection before participation.</li>
	<li>Use the following exclusion criteria: Individuals with a known history of COVID-19 infection; Recent illnesses or flu-like symptoms; Individuals who have had contact with a confirmed case of COVID-19 within the last 14 days; Pregnant or breastfeeding women; Individuals with insufficient sample volume.</li>
	<li>Collect whole blood samples (3-5 mL) from healthy, eligible blood donors. In this study, the blood samples were collected in yellow and red top plain collection tubes at King Abdulaziz University Hospital. We coordinated with the blood donation department to ensure samples were obtained from all eligible donors. These samples were then sent to the laboratory for further analysis.</li>
	<li>Record demographic data, including age, sex, blood group, and nationality, from the KAUH Transfusion Services donation area for all participating donors. 
	NOTE: In this study, 3,825 blood samples were collected from donors at King Abdulaziz University Hospital (KAUH), Jeddah, between December 2019 and December 2020.</li>
	<li>Conduct PCR medical examinations to confirm that participants are free from recent illnesses, particularly flu-like symptoms or recent contact with individuals suspected or confirmed to have COVID-19. Exclude any donors with a positive medical history of SARS-CoV-2 infection, duplicated samples, those with insufficient volume, and unlabeled samples. 
	NOTE: Data can be paused after collection and stored at -20 &#176;C until ready for processing.</li>
</ol>
3. Serum processing
<ol>
	<li>Centrifuge blood samples at 200 x g for 10 min to obtain serum (supernatant). Store the serum at -20 &#176;C in a Biosafety Level 3 facility at SIAU until testing. 
	CAUTION: Ensure proper handling of samples in a Biosafety Level 3 facility.</li>
</ol>
4. In-house enzyme-linked immunosorbent assay (ELISA)
<ol>
	<li>Screen sera samples obtained from healthy blood donors (BDs) for anti-SARS-CoV-2 IgG antibodies using a validated and optimized in-house ELISA19.</li>
	<li>Coat the microtiter plates with 100 ng of SARS-CoV-2 spike recombinant protein diluted in PBS. Incubate the plates overnight at 4 &#176;C.</li>
	<li>Wash the plates 3x with phosphate-buffered saline with Tween 20 (PBST). Block the plates by adding 5% skim milk for 1 h at room temperature. Wash the plates 3x with PBST after blocking.</li>
	<li>Dilute sera samples at 1:100 in 5% skimmed milk. Add 100 &#181;L of diluted sera samples to each well and incubate for 1 h at 37 &#176;C.</li>
	<li>Wash the plates 3x with PBST. Add 100 &#181;L of goat KPL peroxidase-labeled antibodies to human IgG (diluted 1:64,000 in PBST) to each well and incubate for 1 h at 37 &#176;C. Wash the plates 3x with PBST after incubation.</li>
	<li>Add 100 &#181;L of 3,3&#39;,5,5&#39;-Tetramethylbenzidine (TMB) to each well and incubate for 5 min for color development. Add 100 &#181;L of hydrochloric acid to stop the reaction.</li>
	<li>Measure the absorbance at 450 nm using a microplate spectrophotometer. Run all samples in duplicate and use samples from COVID-19-recovered patients as positive controls.</li>
	<li>Consider a specimen reactive (positive) for anti-SARS-CoV-2 IgG antibodies if the optical density (OD 450) value is equal to or greater than 0.27. Consider a specimen non-reactive (negative) if the OD450 value is less than 0.27.</li>
	<li>Subject positive samples to the micro-neutralization assay (MN) as the gold standard for confirmation21.</li>
</ol>
5. Micro-neutralization (MN) assay
NOTE: Conduct all procedures in a Biosafety Level 3 (BSL-3) facility to ensure appropriate handling of infectious agents.
<ol>
	<li>Assess the presence of virus-specific antibodies and measure their neutralization using the MN assay, considered the gold standard method21.</li>
	<li>Heat-inactivate serum samples by placing them in a water bath at 56 &#176;C for 30 min. Prepare serial dilutions of heat-inactivated serum samples at 1:10, 1:20, and 1:40 using Dulbecco&#39;s Modified Eagle Medium (DMEM) containing 100 mL from 50% tissue culture infection dose (TCID 50) of SARS-CoV-2.</li>
	<li>Culture Vero E6 cells in DMEM a starting cell number of 2-3 x 105 cells/well to reach 70%-80% confluency in 24 h. Once confluent, add 100 &#181;L of the diluted serum samples to the wells containing the confluent Vero E6 cells.</li>
	<li>Add 100 &#181;L of DMEM containing 50% tissue culture infection dose (TCID50) of SARS-CoV-2 to each well. Incubate the plates at 37 &#176;C in a 5% CO2 humidified incubator for 3-4 days.</li>
	<li>Assess the cytopathic effect (CPE) 3 days after infection using an inverted microscope to read the plate. Determine MN titers as the highest dilution of the serum sample that completely prevents the viral-induced cytopathic effect. MN titer &#8805; 1:20 is considered positive for the presence of virus-specific antibodies.</li>
	<li>Include wells with SARS-CoV-2-infected cells without human serum as positive controls. Include wells without virus or serum as negative controls.</li>
</ol>
6. Statistical analysis
<ol>
	<li>Use a spreadsheet to organize clinical and diagnostic demographic data for all donor participants and generate charts and graphs for test results.</li>
	<li>Perform statistical analysis using SPSS software to calculate the percentage of variables.
	<ol>
		<li>Present categorical variables such as age group, gender, blood group, and nationality as numbers (n) and percentages (%).</li>
		<li>Present continuous variables, such as donor age, as mean &#177; standard deviation (SD).</li>
	</ol>
	</li>
	<li>Conduct a Chi-square test to examine the association between demographic factors and seroprevalence results.
	<ol>
		<li>If an association is detected, apply a post-hoc Bonferroni test to determine the significant factor.</li>
	</ol>
	</li>
	<li>Define statistical significance as a p-value of less than 0.05.</li>
</ol>

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<li>Dzik, S., Eliason, K., Morris, E. B., Kaufman, R. M., North, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Covid-19+and+abo+blood+groups%5BTitle%5D)+AND+%22Transfusion%22%5BJournal%5D)">Covid-19 and abo blood groups.</a> Transfusion. 60 (8), 1883(2020).</li>
<li>Levi, J. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Lack+of+association+between+abo+blood+groups+and+susceptibility+to+sars-cov-2+infection%5BTitle%5D)+AND+%22Hematol+Transf+Cell+Ther%22%5BJournal%5D)">Lack of association between abo blood groups and susceptibility to sars-cov-2 infection.</a> Hematol Transf Cell Ther. 42, 541(2020).</li>
<li>Focosi, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Anti-a+isohaemagglutinin+titres+and+SARS-CoV-2+neutralization%3A+Implications+for+children+and+convalescent+plasma+selection%5BTitle%5D)+AND+%22Brit+J+Haematol%22%5BJournal%5D)">Anti-a isohaemagglutinin titres and SARS-CoV-2 neutralization: Implications for children and convalescent plasma selection.</a> Brit J Haematol. 190 (3), e148(2020).</li>
<li>Gallian, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Lower+prevalence+of+antibodies+neutralizing+SARS-CoV-2+in+group+O+French+blood+donors%5BTitle%5D)+AND+%22Antiviral+Res%22%5BJournal%5D)">Lower prevalence of antibodies neutralizing SARS-CoV-2 in group O French blood donors.</a> Antiviral Res. 181, 104880(2020).</li>
<li>Leaf, R. K., Al-Samkari, H., Brenner, S. K., Gupta, S., Leaf, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Abo+phenotype+and+death+in+critically+ill+patients+with+covid-19%5BTitle%5D)+AND+%22Brit+J+Haematol%22%5BJournal%5D)">Abo phenotype and death in critically ill patients with covid-19.</a> Brit J Haematol. 190 (4), e204(2020).</li>
<li>Golinelli, D., Boetto, E., Maietti, E., Fantini, M. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((The+association+between+abo+blood+group+and+sars-cov-2+infection%3A+A+meta-analysis%5BTitle%5D)+AND+%22PloS+One%22%5BJournal%5D)">The association between abo blood group and sars-cov-2 infection: A meta-analysis.</a> PloS One. 15 (9), e0239508(2020).</li>
</ol>

The authors declare no conflict of interest.

In response to the COVID-19 pandemic, many countries, including Saudi Arabia, have imposed a variety of control and restriction measures9,23. The impact of these test measures on reducing virus transmission is unknown, and further investigation is needed24. In this study, the prevalence of SARS-CoV-2 in Jeddah was assessed during three consecutive periods of the COVID-19 pandemic (before, during, and after the lockdown period). The results...

Coronavirus disease 2019 (COVID-19), caused by the novel beta-coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a major global health concern due to its devastating outcomes1. The virus is thought to have originated from genetic recombination between bats and pangolins2. The virus was subsequently transmitted to humans, demonstrating efficient human-to-human transmission through aerosols. The first case of COVID-19 was reported on 31 December 2019 in Wuhan, China3. The virus quickly spread across China and subsequently to the rest of the world4. 
The World Health Organization declared SARS-CoV-2 a pandemic on March 11, 2020, with more than 400 million cases reported worldwide in 2022, with 6 million deaths5. The cumulative number of COVID-19 cases reported to WHO has reached more than 776 million worldwide and more than 841,000 in Saudi Arabia6. The number may be much higher because people infected with the disease are asymptomatic or have mild to moderate symptoms, although COVID-19 can cause severe complications such as pneumonia, acute respiratory distress syndrome, and organ failure7. 
This pandemic has affected the entire world; governments and healthcare organizations have been quick to take strict measures since day 1 to limit the spread of the novel coronavirus. These measures include identifying and quarantining suspected and confirmed cases, establishing isolation units, social distancing, widespread use of face masks, and travel restrictions8. Saudi Arabia was also among the first countries to impose strict measures after reporting the first case of novel coronavirus on March 2, 2020. The Ministry of Health and policymakers in Saudi Arabia imposed strict control measures in February 2020, such as closing mosques, closing schools and universities, providing free healthcare to all COVID-19 patients9, evacuating Saudis from affected countries, suspending domestic and international flights, and suspending tourism and Umrah10. These restrictions were gradually eased after May 28, 2020, through a three-phase plan that maintained key measures such as social distancing, face masks, and virtual learning. On December 17, 2020, the Pfizer-BioNTech COVID-19 vaccine became available in Saudi Arabia11.
Multiple studies investigated COVID-19 seroprevalence to identify the true number of asymptomatic infections, which may contribute significantly to disease transmission12,13. Such studies are essential for evaluating herd immunity, an important indicator of virus transmission within populations. Identifying asymptomatic COVID-19 cases is also crucial for preventing and controlling the spread of the virus. Effective control of COVID-19 transmission requires efforts to detect asymptomatic and mildly symptomatic cases who do not seek healthcare and remain undetected by surveillance systems14. Understanding the actual number of infected individuals in a community is essential for estimating the need for measures such as hospitalization rates15. Furthermore, seroprevalence data can help expand knowledge on transmission dynamics and inform suitable control measures, such as social distancing, educational institution closures, and vaccination.
Several studies have explored the antibody response to SARS-CoV-2 infection, considering various factors such as demographics (age, sex, and ethnicity). However, many of these studies have yielded inconsistent or inconclusive results, partly due to differences in study design, strategies, and outcome measures. In particular, while most studies found no correlation between antibody response and age or gender16, some reported conflicting findings that lacked robust statistical analysis. Also, there is also a lack of published data explaining immunological responses across different ethnic groups.
Previous research aimed at identifying the true number of asymptomatic individuals has been conducted on approximately one million blood donors in 20 countries from January 2020 to January 2021. By reviewing thirty-three of these studies, it observed the seroprevalence was less than 10% in 79% of the studies as of December 2020, indicating low herd immunity17. One study conducted in Saudi Arabia, in Al-Madinah, had reported a high prevalence of SARS-CoV-2 antibodies among donors18. Although the study had several limitations, including the absence of confirmatory testing with a standard assay19, it provides an important basis for understanding antibody prevalence and underscores the need for further confirmatory research in this area.
Further investigation was needed to assess the seroprevalence of SARS-CoV-2 across various demographics in multiple cities over extended periods. Given its diverse population, Jeddah-Saudi Arabia's largest city after Riyadh-was of particular interest as a study area. Therefore, our study was expanded beyond its initial scope to include a larger sample size and a more comprehensive analysis of seroprevalence trends across three distinct phases: before, during, and after the lockdown. These expanded efforts aimed to provide a clearer understanding of COVID-19 transmission patterns and the role of blood donors in reflecting community-level antibody prevalence, ultimately guiding future public health strategies.
The significance of this study lies in its contribution to understanding seroprevalence trends among blood donors during three distinct pandemic phases: pre-lockdown, during lockdown, and post-lockdown. Blood donors represent a unique population for such studies due to their generally healthy status and frequent contributions, which can provide valuable insights into asymptomatic or mildly symptomatic infections20. Understanding seroprevalence in this group is crucial for assessing community-level exposure to the virus and its implications for public health planning, including vaccination strategies.
This study hypothesizes that seroprevalence among blood donors will show a marked increase following the easing of lockdown measures, reflecting the delayed spread of SARS-CoV-2 after restrictions were lifted. By comparing pre- and post-lockdown seroprevalence, the research aims to provide insights into the dynamics of COVID-19 transmission and the effectiveness of initial containment measures. Furthermore, this study seeks to explore demographic factors such as gender, age, and nationality to understand their influence on seroprevalence. This research aimed to investigate the seroprevalence of IgG anti-SARS-CoV-2 among BDs from December 2019 to December 2020 at KAUH, Jeddah. The study had three specific objectives: Firstly, to measure the prevalence of IgG antibodies to SARS-CoV-2 in the general population and correlate it with demographic data such as gender, age, blood group, and nationality. Secondly, to determine whether case zero or any early cases were present before the first officially reported case in the country on 2nd March 2020. Thirdly, investigating the dynamics of COVID-19 infection at different time points (before, during, and after the lockdown period).

<table><tbody><tr><td>African green monkey kidney cells Vero E6</td><td>ATCC</td><td>CRL1586</td><td>Cells used for MN assay</td></tr><tr><td>Difco Skim Milk BD Biosciences (5% skim milk with PBST)</td><td>Becton-Dickinson &amp;amp; Company</td><td>232100</td><td>Blocks non-specific binding</td></tr><tr><td>Dulbecco&amp;rsquo;s Modified Eagle Medium (DMEM)</td><td>Gibco by Life Technologies</td><td>2241121</td><td>Growth medium for Vero E6 cells</td></tr><tr><td>Elx 800 Bioelisa Reader</td><td>Biokit</td><td>185681</td><td>Measures absorbance at 450 nm in ELISA assay</td></tr><tr><td>Hydrochloric acid standard solution (HCL)</td><td>Sigma-Aldrich</td><td>7647-01-0</td><td>Stops the color development reaction in ELISA</td></tr><tr><td>Immuno-plate (96-well flat plate)</td><td>SPL Life Sciences</td><td>32296</td><td>Used as the surface for ELISA assay reactions</td></tr><tr><td>Incubator 37 &amp;deg;C</td><td>LabTech</td><td>LIB&amp;ndash;080M</td><td>Incubator for ELISA plate</td></tr><tr><td>Phosphate buffer saline (PBS)</td><td>Sigma-Aldrich</td><td>79382</td><td>Used for sample dilution and washing</td></tr><tr><td>SARS-CoV-2 B.1.617.2 Spike S1+S2 trimer Protein (ECD, His tag) (SARS-CoV-2 full-length spike protein)</td><td>Sino Biological</td><td>40589-V08B1</td><td>Used for coating microtiter plates in ELISA assay to detect SARS-CoV-2 antibodies</td></tr><tr><td>SARS-CoV-2 clinical isolate</td><td>SIAU</td><td>NA</td><td>Virus used for micro-neutralization assay</td></tr><tr><td>Secondary Ab (goat KPL peroxidase-labelled antibodies to human IgG)</td><td>Sera care</td><td>5220-0277</td><td>Secondary antibody to bind and detect human IgG in ELISA</td></tr><tr><td>SureBlue TMB 1-Component Microwell Peroxidase Substrate&amp;nbsp;</td><td>Sera care</td><td>5120-0075</td><td>It is a substrate solution used to bind with secondary antibody and then change the color of the reaction in the ELISA plate</td></tr><tr><td>Tween 20 Surfact -Amps Detergent Solution</td><td>Thermo-Fisher Scientific</td><td>85113</td><td>Adding tween to PBS buffer to make (PBST) as detergent to prevent non-specific binding by washing</td></tr></tbody></table>

covid-19 seroprevalence test for igg antibody levels among healthy donors across different pandemic phases in jeddah

COVID-19 Seroprevalence Test for IgG Antibody Levels Among Healthy Donors Across Different Pandemic Phases in Jeddah

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has significantly impacted global public health and the economy. This study aimed to investigate the seroprevalence of IgG antibodies against SARS-CoV-2 among healthy blood donors in Jeddah, Saudi Arabia, to better understand the dynamics of COVID-19 transmission during three distinct periods: pre-lockdown, during-lockdown, and post-lockdown. The seroprevalence was assessed concerning demographic factors such as gender, age, blood group, and nationality. A cross-sectional study was conducted from December 2019 to December 2020. A total of 3,825 blood samples from healthy donors were screened using an in-house enzyme-linked immunosorbent assay (ELISA) for anti-SARS-CoV-2 IgG antibodies detection. Positive samples were further confirmed using a micro-neutralization (MN) assay. Of 3,825 serum samples, 173 (4.5%) were tested positive by ELISA, and 147 samples were confirmed positive by MN. All samples collected before the lockdown (December 2019 to February 2020) were negative for IgG antibodies. During the lockdown period (March 2020 to June 2020), 44 out of 1,482 samples (2.97%) were tested positive. After the lockdown was eased (July 2020 to December 2020), the positivity rate increased to 12.15% (103 out of 848 samples). The overall seroprevalence rate among healthy blood donors was 3.84%, with significantly higher rates among non-Saudi and male donors (p = 0.00). The findings suggest that COVID-19 restrictions implemented by the Saudi authorities were effective in reducing the initial spread of the virus. However, the marked increase in seroprevalence over time suggests that asymptomatic or mildly symptomatic individuals may pose a significant risk for continued transmission. Continuous monitoring of seroprevalence is essential to control the spread of COVID-19.

The socio-demographic characteristics of blood donor participants were analyzed from 3,825 blood samples collected at King Abdulaziz University Hospital (KAUH), Jeddah, Saudi Arabia, between December 2019 and December 2020, to evaluate the seroprevalence of COVID-19 antibodies. This period was divided into three distinct phases: pre-lockdown (December 2019 to February 2020), during lockdown (March 2020 to June 2020), and post-lockdown (July 2020 to December 2020). The number of blood donors varied across these phases: 1,...

This study assessed COVID-19 seroprevalence in Jeddah, Saudi Arabia, among healthy blood donors across pre-lockdown, during-lockdown, and post-lockdown periods. Of 3,825 samples, 4.5% tested positive for IgG antibodies. Seroprevalence increased significantly post-lockdown, highlighting the role of asymptomatic transmission and the effectiveness of initial restrictions.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has significantly impacted global public ...

This research examined the IgG seroprevalence in healthy Jeddah donors across the early COVID-19 pandemic to assessing the immunity after, during, and before lockdown. Our research uses ELISA, PCR, and high-throughput serology platform and statistical modelings tool to measure antibody level and in the medium. To begin, obtain blood samples from healthy patients who do not have any history of COVID-19.Centrifuge the samples at 200 G for 10 minutes to obtain the serum supernatant. Store at minus 20 degrees Celsius in a biosafety level three facility at the SIAU until testing. To screen for anti-SARS-CoV-2 IgG antibodies, coat microtiter plates with 100 nanograms of SARS-CoV-2 spike recombinant protein diluted in PBS.Incubate the plates overnight at four degrees Celsius. Wash the plates three times with PBST, then add 5%skim milk to block the plates and incubate. Wash the plates three more times with PBST after blocking.Now, dilute the sera samples at a ratio of one to 100 in 5%skim milk. Add 100 microliters of diluted sera into each well. Then, incubate the plate at 37 degrees Celsius for one hour.After washing the plates three more times with PBST, pipette each well with 100 microl

covid-19-seroprevalence-test-for-igg-antibody-levels-among-healthy

Research

JoVE Journal

Immunology and Infection

In the current climate of scarce resources, new technologies are emerging that allow researchers to conduct studies cheaper, faster and with more precision. Here we describe the development of a bead-based salivary antibody multiplex immunoassay to measure human exposure to multiple environmental pathogens simultaneously.

Developing a Salivary Antibody Multiplex Immunoassay to Measure Human Exposure to Environmental Pathogens

The protocol described here outlines a fast and effective method for measuring neutralizing antibodies against the SARS-CoV-2 spike protein by evaluating the ability of convalescent serum samples to inhibit infection by an enhanced green fluorescent protein-labeled vesicular stomatitis virus pseudotyped with spike glycoprotein.

Detection of SARS-CoV-2 Neutralizing Antibodies using High-Throughput Fluorescent Imaging of Pseudovirus Infection

A flow analysis system for bead-based multiplexed assays which provides a two-reporter readout was used for the development of multiplex serological and antibody neutralization assays that can simultaneously measure neutralizing IgG and IgM antibodies for SARS-CoV-2.

A Rapid, Multiplex Dual Reporter IgG and IgM SARS-CoV-2 Neutralization Assay for a Multiplexed Bead-Based Flow Analysis System

The outlined protocol describes the procedure for producing the HiBiT-receptor-binding domain protein complex and its application for fast and sensitive detection of SARS-CoV-2 antibodies.

Detection of SARS-CoV-2 Receptor-Binding Domain Antibody using a HiBiT-Based Bioreporter

This article describes a convenient method for monitoring dynamic changes in antibody titers for two immunoglobulin isotypes concurrently (either IgA, IgM, or IgG) resulting from an immune response to SARS-CoV-2 infection or vaccination. This 'Multianalyte Covid-19 Immune Response Panel' employs three indirect immunoassays built on coded microspheres that are read using a flow-based multiplex reader with 'dual-channel' capability.

Dynamic Monitoring of Seroconversion using a Multianalyte Immunobead Assay for Covid-19

In line with the urgent need for screening for type 1 diabetes, celiac disease, and coronavirus disease 2019, we developed a high throughput 6-Plex electrochemiluminescence assay to simultaneously detect all four islet autoantibodies, tissue transglutaminase autoantibodies, and antibodies to the receptor binding domain of severe acute respiratory syndrome coronavirus 2.

A High-Throughput Multiplexed Screening for Type 1 Diabetes, Celiac Diseases, and COVID-19

A three-channel dual-reporter fluorescence flow analysis system was used to develop a bead-based multiplex immunoassay that simultaneously evaluates serum samples for IgG and IgM elicited against multiple antigens of different Borrelia species that cause Lyme borreliosis in Europe and North America.

Simultaneous Detection of Different Antibody Classes in a Multiplexed Serological Test

The aim of this manuscript is to examine the use of the rabies indirect fluorescent antibody test for the detection of rabies-specific IgG and IgM antibodies.

Detection of Rabies IgG and IgM Antibodies Using the Rabies Indirect Fluorescent Antibody Test

We describe a recently developed immunoassay platform based on the principles of cell-free synthetic biology and the dot-blot technique for customizable detection of antibody response in human and animal sera.

Cell-Free Dot Blot as a Practical and Adaptable Immunoassay Platform for the Detection of Antibody Response in Human and Animal Sera

Multiplex fluorescence immunoassays are becoming a reference for serology testing. Their application, however, is limited by the complexity and time-consuming bead-analyte coupling processes. This report presents a semi-automated, reproducible multiplex microsphere bead coupling protocol that is comparable to the standard method while considerably reducing time to results.

A Multiplex Serological Assay for the Detection of Antibody Responses to Arboviruses

Discover COVID-19 IgG seroprevalence patterns among healthy Jeddah donors across pre-lockdown, during-lockdown, and post-lockdown phases using ELISA and PCR methods. This study reveals 4.5% antibody positivity with significant post-lockdown increases.

COVID-19 Seroprevalence Test for IgG Antibody Levels Among Healthy Donors Across Different Pandemic Phases in Jeddah

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