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Jie H, Wang Y, Zhao M, Wang X, Wang Z, Zeng L, Cao X, Xu T, Xia F, Liu Q. Automatic ultrasensitive lateral flow immunoassay based on a color-enhanced signal amplification strategy. Biosens Bioelectron 2024; 256:116262. [PMID: 38621340 DOI: 10.1016/j.bios.2024.116262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 02/27/2024] [Accepted: 03/29/2024] [Indexed: 04/17/2024]
Abstract
Lateral flow immunoassays (LFIAs) are an essential and widely used point-of-care test for medical diagnoses. However, commercial LFIAs still have low sensitivity and specificity. Therefore, we developed an automatic ultrasensitive dual-color enhanced LFIA (DCE-LFIA) by applying an enzyme-induced tyramide signal amplification method to a double-antibody sandwich LFIA for antigen detection. The DCE-LFIA first specifically captured horseradish peroxidase (HRP)-labeled colored microspheres at the Test line, and then deposited a large amount of tyramide-modified signals under the catalytic action of HRP to achieve the color superposition. A limit of detection (LOD) of 3.9 pg/mL and a naked-eye cut-off limit of 7.8 pg/mL were achieved for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleoprotein. Additionally, in the inactivated virus detections, LOD equivalent to chemiluminescence (0.018 TCID50/mL) was obtained, and it had excellent specificity under the interference of other respiratory viruses. High sensitivity has also been achieved for detection of influenza A, influenza B, cardiac troponin I, and human chorionic gonadotrophin using this DCE-LFIA, suggesting the assay is universally applicable. To ensure the convenience and stability in practical applications, we created an automatic device. It provides a new practical option for point-of-care test immunoassays, especially ultra trace detection and at-home testing.
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Affiliation(s)
- Huiyang Jie
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China
| | - Yu Wang
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China
| | - Meng Zhao
- Micro-nano Tech Center, Bioland Laboratory, Guangzhou, Guangdong, 510000, PR China
| | - Xiuzhen Wang
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China
| | - Zhong Wang
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China
| | - Lingliao Zeng
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China
| | - Xiaobao Cao
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China.
| | - Tao Xu
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China; School of Biomedical Engineering, Guangzhou Medical University, Guangzhou, Guangdong, 511436, PR China
| | - Fan Xia
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan, Hubei, 430074, PR China
| | - Qian Liu
- Department of Detection and Diagnosis Technology Research, Guangzhou National Laboratory, Guangzhou, Guangdong, 510000, PR China; School of Biomedical Engineering, Guangzhou Medical University, Guangzhou, Guangdong, 511436, PR China.
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Geißler D, Wegner KD, Fischer C, Resch-Genger U. Exploring Simple Particle-Based Signal Amplification Strategies in a Heterogeneous Sandwich Immunoassay with Optical Detection. Anal Chem 2024; 96:5078-5085. [PMID: 38498677 PMCID: PMC10993196 DOI: 10.1021/acs.analchem.3c03691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 02/28/2024] [Accepted: 02/28/2024] [Indexed: 03/20/2024]
Abstract
Heterogeneous sandwich immunoassays are widely used for biomarker detection in bioanalysis and medical diagnostics. The high analyte sensitivity of the current "gold standard" enzyme-linked immunosorbent assay (ELISA) originates from the signal-generating enzymatic amplification step, yielding a high number of optically detectable reporter molecules. For future point-of-care testing (POCT) and point-of-need applications, there is an increasing interest in more simple detection strategies that circumvent time-consuming and temperature-dependent enzymatic reactions. A common concept to aim for detection limits comparable to those of enzymatic amplification reactions is the usage of polymer nanoparticles (NP) stained with a large number of chromophores. We explored different simple NP-based signal amplification strategies for heterogeneous sandwich immunoassays that rely on an extraction-triggered release step of different types of optically detectable reporters. Therefore, streptavidin-functionalized polystyrene particles (PSP) are utilized as carriers for (i) the fluorescent dye coumarin 153 (C153) and (ii) hemin (hem) molecules catalyzing the luminol reaction enabling chemiluminescence (CL) detection. Additionally, (iii) NP labeling with hemin-based microperoxidase MP11 was assessed. For each amplification approach, the PSP was first systematically optimized regarding size, loading concentration, and surface chemistry. Then, for an immunoassay for the inflammation marker C-reactive protein (CRP), the analyte sensitivity achievable with optimized PSP systems was compared with the established ELISA concept for photometric and CL detection. Careful optimization led to a limit of detection (LOD) of 0.1 ng/mL for MP11-labeled PSP and CL detection, performing similarly well to a photometric ELISA (0.13 ng/mL), which demonstrates the huge potential of our novel assay concept.
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Affiliation(s)
| | | | | | - Ute Resch-Genger
- Division Biophotonics, Federal Institute for Materials Research and Testing
(BAM), Richard-Willstaetter-Str. 11, 12489 Berlin, Germany
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Li Q, Wang Y, Liu H, Peng H, Xiang J, Guo S. Imaging Progression Under Low Respiratory Viral Load of SARS-CoV-2 Omicron Variant Infection: A Retrospective Study in China. Infect Drug Resist 2023; 16:6795-6806. [PMID: 37904829 PMCID: PMC10613413 DOI: 10.2147/idr.s417062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/21/2023] [Indexed: 11/01/2023] Open
Abstract
Purpose To investigate the computed tomography (CT) findings of SARs-CoV-2 Omicron variant in relation to respiratory viral loads determined by cycle threshold values in reverse-transcription polymerase chain reaction (RT-PCR). Materials and Methods From October 2022 to November 2022, 74 hospitalized patients with Omicron were included in this retrospective study. The radiological features, CT involvement scores in relation to the respiratory viral load, and factors associated with imaging progression (IP) after the RT-PCR results turned negative were analyzed. Results The most common CT patterns of Omicron were multiple round-like or patchy ground-glass opacity (GGO) or mixed GGO in the peripheral or diffuse areas. The grading of CT involvement scores exhibited an inverse pattern compared to viral loads from day 1 to day 8 and from day 13 to day 20 after diagnosis. Among the 65 patients with complete imaging data, 45 (69.23%) showed IP with clinical warning indicators of disease exacerbation negative in 34 and positive in 11. Patients with IP were older than those with non-IP (NIP); the erythrocyte sedimentation rates, procalcitonin levels, and D-dimer levels on admission of patients with IP were significantly higher than those of patients with NIP, whereas the immunoglobulin (Ig) G antibody level on admission and CT involvement score on initial CT of patients with IP were significantly lower than those of patients with NIP (all P < 0.05). Conclusion For patients with Omicron, the IP of lung abnormalities is common when the viral load decreases. Under these circumstances, paying attention to clinical warming indicators of disease progression may contribute to better patient management and the mitigation of severe pneumonia.
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Affiliation(s)
- Qi Li
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, People’s Republic of China
| | - Yongli Wang
- Department of Infectious Disease, Chongqing University Three Gorges Hospital, Chongqing, 404000, People’s Republic of China
| | - Huawen Liu
- Department of Oncology, Chongqing University Three Gorges Hospital, Chongqing, 404000, People’s Republic of China
| | - Hailang Peng
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, People’s Republic of China
| | - Jianglin Xiang
- Department of Infectious Disease, Chongqing University Three Gorges Hospital, Chongqing, 404000, People’s Republic of China
| | - Shuliang Guo
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, People’s Republic of China
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Liu M, Liang Z, Cheng ZJ, Liu L, Liu Q, Mai Y, Chen H, Lei B, Yu S, Chen H, Zheng P, Sun B. SARS-CoV-2 neutralising antibody therapies: Recent advances and future challenges. Rev Med Virol 2023; 33:e2464. [PMID: 37322826 DOI: 10.1002/rmv.2464] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 05/01/2023] [Accepted: 05/30/2023] [Indexed: 06/17/2023]
Abstract
The COVID-19 pandemic represents an unparalleled global public health crisis. Despite concerted research endeavours, the repertoire of effective treatment options remains limited. However, neutralising-antibody-based therapies hold promise across an array of practices, encompassing the prophylaxis and management of acute infectious diseases. Presently, numerous investigations into COVID-19-neutralising antibodies are underway around the world, with some studies reaching clinical application stages. The advent of COVID-19-neutralising antibodies signifies the dawn of an innovative and promising strategy for treatment against SARS-CoV-2 variants. Comprehensively, our objective is to amalgamate contemporary understanding concerning antibodies targeting various regions, including receptor-binding domain (RBD), non-RBD, host cell targets, and cross-neutralising antibodies. Furthermore, we critically examine the prevailing scientific literature supporting neutralising antibody-based interventions, and also delve into the functional evaluation of antibodies, with a particular focus on in vitro (vivo) assays. Lastly, we identify and consider several pertinent challenges inherent to the realm of COVID-19-neutralising antibody-based treatments, offering insights into potential future directions for research and development.
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Affiliation(s)
- Mingtao Liu
- Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zhiman Liang
- Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zhangkai J Cheng
- Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Li Liu
- Guangzhou Medical University, Guangzhou, China
| | - Qiwen Liu
- Guangzhou Medical University, Guangzhou, China
| | - Yiyin Mai
- Guangzhou Medical University, Guangzhou, China
| | | | - Baoying Lei
- Guangzhou Medical University, Guangzhou, China
| | - Shangwei Yu
- Guangzhou Medical University, Guangzhou, China
| | - Huihui Chen
- Guangzhou Medical University, Guangzhou, China
| | - Peiyan Zheng
- Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Baoqing Sun
- Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
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Lim YK, Kweon OJ, Choi Y, Yoon S, Kim TH, Lee MK. Exploring the vaccine-induced immunity against severe acute respiratory syndrome coronavirus 2 in healthcare workers. Sci Rep 2023; 13:6830. [PMID: 37100845 PMCID: PMC10131514 DOI: 10.1038/s41598-023-33397-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 04/12/2023] [Indexed: 04/28/2023] Open
Abstract
We aimed to analyze the kinetics of T-cell-mediated and B-cell-mediated humoral immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before and after booster vaccination, as well as the impacts of the in vitro test results the type of vaccination on the prediction of SARS-CoV-2 infection. A total of 240 healthcare workers vaccinated twice were serially tested using an interferon gamma release assay (IGRA) and a neutralizing antibody (nAb). At the end of the study, we investigated the history of SARS-CoV-2 infection of all the enrolled participants to analyze the effects of the test results and the type of vaccination on SARS-CoV-2 infection. Overall, the positive rates were 52.3% and 80.0% for IGRA and 84.6% and 100% for the nAb test before and after booster vaccination, respectively. However, the positive rates were 52.8% for IGRA and 100% for nAb 3 months after booster vaccination. The in vitro test results and the type of vaccination were not associated with SARS-CoV-2 infection. The antibody response caused by the SARS-CoV-2 vaccination lasted more than 6 months, although the response of the T-cells disappeared rapidly after 3 months. However, these in vitro results and the type of vaccination cannot be used for predicting the risk of SARS-CoV-2 infection.
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Affiliation(s)
- Yong Kwan Lim
- Department of Laboratory Medicine, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, South Korea
| | - Oh Joo Kweon
- Department of Laboratory Medicine, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, South Korea
| | - Yoojeong Choi
- Department of Laboratory Medicine, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, South Korea
| | - Sumi Yoon
- Department of Laboratory Medicine, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, South Korea
| | - Tae-Hyoung Kim
- Department of Urology, Chung-Ang University College of Medicine, Seoul, South Korea
| | - Mi-Kyung Lee
- Department of Laboratory Medicine, Chung-Ang University College of Medicine, 102 Heukseok-ro, Dongjak-gu, Seoul, 06973, South Korea.
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Jurenka J, Nagyová A, Dababseh M, Mihalov P, Stankovič I, Boža V, Kravec M, Palkovič M, Čaprnda M, Sabaka P. Anti-SARS-CoV-2 Antibody Status at the Time of Hospital Admission and the Prognosis of Patients with COVID-19: A Prospective Observational Study. Infect Dis Rep 2022; 14:1004-1016. [PMID: 36547246 PMCID: PMC9779184 DOI: 10.3390/idr14060100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/05/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
The association between COVID-19 severity and antibody response has not been clearly determined. We aimed to assess the effects of antibody response to SARS-CoV-2 S protein at the time of hospital admission on in-hospital and longitudinal survival. Methods: A prospective observational study in naive hospitalised COVID-19 patients. The presence of anti-S SARS-CoV-2 IgM and IgG was evaluated using a lateral flow assay at the time of admission. The patients were followed up for 8-30 months to assess survival. We recruited 554 patients (330 men and 224 women). Overall, 63.0% of the patients had positive IgG or IgM anti-S SARS-CoV-2 antibodies at the time of hospital admission. In the univariate analysis, the patients with negative anti-S SARS-CoV-2 IgM and IgG antibodies were referred to the hospital sooner, had lower CRP and D-dimer concentrations, and were hospitalised longer. They were also more likely to be admitted to an intensive care unit and more often received baricitinib treatment. During their hospital stay, 8.5% of the antibody-positive and 22.3% of the antibody-negative patients died (p = 0.0001). The median duration of the follow-up was 21 months. During the follow-up after hospital discharge, 3.6% of antibody-positive and 9.1% of antibody-negative patients died (p = 0.027). In the multivariate analysis, the negative anti-S SARS-CoV-2 antibodies were associated with a higher risk of in-hospital death (OR 3.800; 95% CI 1.844-7.829; p = 0.0001) and with a higher risk of death during follow-up (OR 2.863; 95% CI 1.110-7.386; p = 0.030). These associations were independent of age, the time from symptom onset to hospital admission, CRP, D-Dimer, the number of comorbidities, disease severity at the time of hospital admission, and baricitinib therapy. Our study concludes that negative anti-S SARS-CoV-2 IgM and IgG at the time of admission are associated with higher in-hospital mortality and cause a higher risk of all-cause death during follow-up after discharge.
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Affiliation(s)
- Ján Jurenka
- Department of Infectology and Geographical Medicine, Faculty of Medicine, Comenius University in Bratislava, 831 01 Bratislava, Slovakia
| | - Anna Nagyová
- Department of Infectology and Geographical Medicine, Faculty of Medicine, Comenius University in Bratislava, 831 01 Bratislava, Slovakia
| | - Mohammad Dababseh
- Department of Infectology and Geographical Medicine, Faculty of Medicine, Comenius University in Bratislava, 831 01 Bratislava, Slovakia
| | - Peter Mihalov
- Department of Infectology and Geographical Medicine, Faculty of Medicine, Comenius University in Bratislava, 831 01 Bratislava, Slovakia
| | - Igor Stankovič
- Department of Infectology and Geographical Medicine, Faculty of Medicine, Comenius University in Bratislava, 831 01 Bratislava, Slovakia
| | - Vladimír Boža
- Department of Applied Informatics, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, 842 48 Bratislava, Slovakia
| | - Marián Kravec
- Department of Applied Informatics, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, 842 48 Bratislava, Slovakia
| | - Michal Palkovič
- Department of Pathology, Faculty of Medicine, Comenius University in Bratislava, 811 08 Bratislava, Slovakia
| | - Martin Čaprnda
- 1st Department of Internal Medicine, Faculty of Medicine, Comenius University in Bratislava, 811 08 Bratislava, Slovakia
| | - Peter Sabaka
- Department of Infectology and Geographical Medicine, Faculty of Medicine, Comenius University in Bratislava, 831 01 Bratislava, Slovakia
- Correspondence:
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Lu C, Lopez A, Zheng J, Liu J. Using the Intrinsic Fluorescence of DNA to Characterize Aptamer Binding. Molecules 2022; 27:molecules27227809. [PMID: 36431910 PMCID: PMC9692703 DOI: 10.3390/molecules27227809] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/08/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022]
Abstract
The reliable, readily accessible and label-free measurement of aptamer binding remains a challenge in the field. Recent reports have shown large changes in the intrinsic fluorescence of DNA upon the formation of G-quadruplex and i-motif structures. In this work, we examined whether DNA intrinsic fluorescence can be used for studying aptamer binding. First, DNA hybridization resulted in a drop in the fluorescence, which was observed for A30/T30 and a 24-mer random DNA sequence. Next, a series of DNA aptamers were studied. Cortisol and Hg2+ induced fluorescence increases for their respective aptamers. For the cortisol aptamer, the length of the terminal stem needs to be short to produce a fluorescence change. However, caffeine and adenosine failed to produce a fluorescence change, regardless of the stem length. Overall, using the intrinsic fluorescence of DNA may be a reliable and accessible method to study a limited number of aptamers that can produce fluorescence changes.
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Affiliation(s)
- Chang Lu
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Anand Lopez
- Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Jinkai Zheng
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Juewen Liu
- Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
- Correspondence:
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Benites BD, Costa-Lima C, Pinto FBR, da Costa VA, Duarte ADSS, Zangirolami AB, Amaro EC, Granja F, Proenca-Modena JL, Saad STO, Addas-Carvalho M. Selection of plasma donors for the production of anti-SARS-CoV-2 immunoglobulin-based therapies: Strategies for quantitative antibody measurements. Transfus Apher Sci 2022; 61:103513. [PMID: 35871137 PMCID: PMC9293395 DOI: 10.1016/j.transci.2022.103513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 07/02/2022] [Accepted: 07/16/2022] [Indexed: 01/04/2023]
Abstract
Even after two years of the pandemic, a completely effective treatment against SARS-CoV-2 has not yet been established. Considering this fact and the emergence of successive new viral variants, the development of therapies based on natural polyclonal antibodies recovered from convalescent plasma remains relevant. This study presents a comparison between different methods of screening antibodies in samples of 41 individuals previously diagnosed with COVID-19. We found a significant correlation between Abbot Architect anti-SARS-CoV-2 IgG and Abbott Allinity SARS-CoV-2 IgG II Quantitative assay intensity of reactivity and neutralizing antibody (nAb) titers. Thus, we propose an initial antibody screening with IgG anti-N Abbott Architect test, with an index of, for example, > 3.25 or SARS-CoV-2 IgG II Quantitative Abbott Allinity assay > 137.65 AU/mL as good predictors of Nab ≥ 1:80. For the quantitative method, this threshold demonstrated a 100 % sensitivity and 80 % specificity, with 97.3 % accuracy. An interesting observation was the increase in the neutralizing activity of the anti-SARS-CoV-2 antibodies with the longest interval between the end of the symptoms and the collection, demonstrating that the delay in plasma collection does not affect the achievement of adequate nAbs levels. These results demonstrate the possibility of using faster and more widely available commercial serological tests with a good correlation with viral neutralization tests in culture, allowing for optimized large-scale donor selection, which will be of utmost importance for the development of therapies such as hyperimmune immunoglobulin.
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Affiliation(s)
| | | | | | | | | | | | | | - Fabiana Granja
- Laboratory of Emerging Viruses (LEVE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Brazil; Biodiversity Research Centre, Federal University of Roraima, Boa Vista, Brazil
| | - José Luiz Proenca-Modena
- Laboratory of Emerging Viruses (LEVE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Brazil
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