scholarly journals Rapid 'mix and read' assay for scalable detection of SARS-CoV-2 antibodies in patient plasma

Author(s):  
Hong Yue ◽  
Radosław P Nowak ◽  
Daan Overwijn ◽  
N Connor Payne ◽  
Stephanie Fischinger ◽  
...  

The human beta coronavirus SARS-CoV-2, causative virus of COVID-19, has infected more than 15 million people globally and continues to spread. Widespread, population level testing to detect active and past infections is critical to curb the COVID-19 pandemic. Antibody (serological) testing is the only option for detecting past infections outside the narrow window accessible to nucleic acid-based tests. However, currently available serological assays commonly lack scalability. Here, we describe the development of a rapid homogenous serological assay for the detection of antibodies to SARS-CoV-2 in patient plasma. We show that the fluorescence-based assay accurately detects seroconversion in COVID-19 patients from less than 1 microliter of plasma. Using a cohort of samples from COVID-19 infected or healthy individuals, we demonstrate detection with 100% sensitivity and specificity. This assay addresses an important need for a robust, low barrier to implementation, and scalable serological assay with complementary strengths to currently available serological platforms.

2010 ◽  
Vol 2 ◽  
pp. BIC.S6040 ◽  
Author(s):  
Yulia A. Savitskaya ◽  
Genaro Rico ◽  
Luis Linares ◽  
Roberto González ◽  
René Téllez ◽  
...  

Background Tumor immunology research has led to the identification of a number of tumor-associated self antigens, suggesting that most tumors trigger an immunogenic response, as is the case in osteosarcoma, where the detection of natural serum IgM antibodies might achieve the diagnosis of osteosarcoma. Natural IgM antibodies to tumor-associated proteins may expand the number of available tumor biomarkers for osteosarcoma and may be used together in a serum profile to enhance test sensitivity and specificity. Natural IgM antibodies can be consistently detected in the peripheral blood sera months to years before the tumor is diagnosed clinically. The study of the level of a potential biomarker many months (or years) prior to diagnosis is fundamentally important. Integrated circulating and imaging markers in clinical practice treating osteosarcoma have potential applications for controlling tumor angiogenesis. Objectives To study the expression of natural IgM antibodies to the tumor antigens of angiogenesis in the peripheral blood sera of osteosarcoma patients and healthy individuals, and to develop serum-based predictive biomarkers. Methods Peripheral venous blood samples were collected from 117 osteosarcoma patients and 117 patients with other tumors. All diagnosis was histologically confirmed. Staging of patients was performed according to the Enneking Surgical Staging System. The control group consisted of 117 age- and sex- matched healthy individuals. In this study, novel immunoconjugates were designed, synthesized and then used to develop a rapid, specific and sensitive enzyme-linked immunosorbent assay (ELISA) method to detect angiogenin (ANG)–IgM directly in the peripheral blood sera of humans. Results Serum ANG–IgM levels are significantly higher in osteosarcoma patients than in healthy individuals ( P < 0.005). Serum ANG–IgM levels varied widely, but were highly dependent on the concentration of IgM (r = 0.85; P < 0.0005). We found ANG–IgM in the sera of 85% of newly diagnosed osteosarcoma patients and ANG–IgM levels were significantly higher in osteosarcoma patients compared to any other tumors ( P < 0.001). Conclusions These results demonstrated that the combined biomarker ANG–IgM has greater sensitivity and specificity in early diagnosis of osteosarcoma patients than the traditional biomarkers (ANG and vascular endothelial growth factor). Circulating ANG–IgM immune complexes can potentially serve as a biomarker for increased risk of osteosarcoma, because relatively high serum levels were also detected in otherwise healthy individuals with a first degree family history of osteosarcoma and in patients with a diagnosis of benign conditions. Immunological aspects of angiogenesis for managing osteosarcoma will have a practical value in early diagnosis, prognosis and monitoring response to antiangiogenic therapy.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Sheng-Li Yang ◽  
Xiefan Fang ◽  
Zao-Zao Huang ◽  
Xiang-Jie Liu ◽  
Zhi-Fan Xiong ◽  
...  

Objective. This review is to evaluate the diagnostic value of serum GPC3 for hepatocellular carcinoma (HCC) due to conflicting results reported.Methods. NCBI PubMed and Embase were comprehensively searched for studies that have used serum GPC3 level as a diagnostic index for HCC. The quality of the included studies was assessed. Subgroup analyses were conducted to evaluate the sensitivity and specificity of GPC3 as a HCC marker. Statistical analysis was performed with the software STATA version 12.0.Results. A total of 22 studies were included. The qualities of included studies were relatively poor. Among them, 18 studies have shown that serum GPC3 is a specific biomarker for HCC, and the pooled sensitivity and specificity of these studies were 69 and 93%, respectively. The other 4 studies have reported conflicting results, which were not caused by races, infection status of HBV and HCV, or assay reagents but due to one common experimental design of enrolling liver cirrhosis patients as control subjects.Conclusions. This meta-analysis indicates that serum GPC3 is elevated in HCC patients compared with healthy individuals, but more studies are needed to evaluate its effectiveness to differentially diagnose HCC and liver cirrhosis.


2017 ◽  
Vol 114 (38) ◽  
pp. E7929-E7938 ◽  
Author(s):  
Maria Paraskevaidi ◽  
Camilo L. M. Morais ◽  
Kássio M. G. Lima ◽  
Julie S. Snowden ◽  
Jennifer A. Saxon ◽  
...  

The progressive aging of the world’s population makes a higher prevalence of neurodegenerative diseases inevitable. The necessity for an accurate, but at the same time, inexpensive and minimally invasive, diagnostic test is urgently required, not only to confirm the presence of the disease but also to discriminate between different types of dementia to provide the appropriate management and treatment. In this study, attenuated total reflection FTIR (ATR-FTIR) spectroscopy combined with chemometric techniques were used to analyze blood plasma samples from our cohort. Blood samples are easily collected by conventional venepuncture, permitting repeated measurements from the same individuals to monitor their progression throughout the years or evaluate any tested drugs. We included 549 individuals: 347 with various neurodegenerative diseases and 202 age-matched healthy individuals. Alzheimer’s disease (AD;n= 164) was identified with 70% sensitivity and specificity, which after the incorporation of apolipoprotein ε4 genotype (APOEε4) information, increased to 86% when individuals carried one or two alleles of ε4, and to 72% sensitivity and 77% specificity when individuals did not carry ε4 alleles. Early AD cases (n= 14) were identified with 80% sensitivity and 74% specificity. Segregation of AD from dementia with Lewy bodies (DLB;n= 34) was achieved with 90% sensitivity and specificity. Other neurodegenerative diseases, such as frontotemporal dementia (FTD;n= 30), Parkinson’s disease (PD;n= 32), and progressive supranuclear palsy (PSP;n= 31), were included in our cohort for diagnostic purposes. Our method allows for both rapid and robust diagnosis of neurodegeneration and segregation between different dementias.


Parasitology ◽  
2018 ◽  
Vol 145 (14) ◽  
pp. 1938-1948 ◽  
Author(s):  
Lígia Moraes Barizon de Souza ◽  
Vanete Thomaz Soccol ◽  
Ricardo Rasmussen Petterle ◽  
Michelle D. Bates ◽  
Paul A. Bates

AbstractOligosaccharides are broadly present onLeishmaniacell surfaces. They can be useful for the leishmaniases diagnosis and also helpful in identifying new cell markers for the disease. The disaccharide Galα1-3Galβis the immunodominant saccharide inLeishmaniacell surface and is the unique non-reducing terminal glycosphingolipids structure recognized by anti-α-Gal. This study describes an enzyme-linked immunosorbent assay (ELISA) used to measure serum levels of anti-α-galactosyl (α-Gal) antibodies in patients with cutaneous leishmaniasis (CL). Optimal ELISA conditions were established and two neoglycoproteins (NGP) containing the Galα1-3Gal terminal fraction (Galα1-3Galβ1-4GlcNAc-HAS and Galα1-3Gal-HAS) and one Galα1-3Gal NGP analogue (Galα1-3Galβ1-3GlcNAc-HAS) were used as antigens. Means of anti-α-Gal antibody titres of CL patients were significantly higher (P< 0.05) than the healthy individuals for all NGPs tested. Sensitivity and specificity of all NGPs ranged from 62.2 to 78.4% and 58.3 to 96.7%, respectively. In conclusion, the NGPs can be used for CL diagnosis.


2020 ◽  
Vol 117 (41) ◽  
pp. 25722-25731 ◽  
Author(s):  
Rose A. Lee ◽  
Helena De Puig ◽  
Peter Q. Nguyen ◽  
Nicolaas M. Angenent-Mari ◽  
Nina M. Donghia ◽  
...  

Asymptomatic carriers ofPlasmodiumparasites hamper malaria control and eradication. Achieving malaria eradication requires ultrasensitive diagnostics for low parasite density infections (<100 parasites per microliter blood) that work in resource-limited settings (RLS). Sensitive point-of-care diagnostics are also lacking for nonfalciparum malaria, which is characterized by lower density infections and may require additional therapy for radical cure. Molecular methods, such as PCR, have high sensitivity and specificity, but remain high-complexity technologies impractical for RLS. Here we describe a CRISPR-based diagnostic for ultrasensitive detection and differentiation ofPlasmodium falciparum,Plasmodium vivax,Plasmodium ovale, andPlasmodium malariae, using the nucleic acid detection platform SHERLOCK (specific high-sensitivity enzymatic reporter unlocking). We present a streamlined, field-applicable, diagnostic comprised of a 10-min SHERLOCK parasite rapid extraction protocol, followed by SHERLOCK for 60 min forPlasmodiumspecies-specific detection via fluorescent or lateral flow strip readout. We optimized one-pot, lyophilized, isothermal assays with a simplified sample preparation method independent of nucleic acid extraction, and showed that these assays are capable of detection below two parasites per microliter blood, a limit of detection suggested by the World Health Organization. OurP. falciparumandP. vivaxassays exhibited 100% sensitivity and specificity on clinical samples (5P. falciparumand 10P. vivaxsamples). This work establishes a field-applicable diagnostic for ultrasensitive detection of asymptomatic carriers as well as a rapid point-of-care clinical diagnostic for nonfalciparum malaria species and low parasite densityP. falciparuminfections.


2001 ◽  
Vol 47 (9) ◽  
pp. 1649-1659 ◽  
Author(s):  
Nobuhide Hayashi ◽  
Tomoko Kawamoto ◽  
Masahiko Mukai ◽  
Akio Morinobu ◽  
Masahiro Koshiba ◽  
...  

Abstract Background: A new enzyme immunoassay (EIA) for automated detection of antinuclear antibodies (ANAs) uses a mixture of HEp-2 cell extracts and multiple recombinant nuclear antigens immobilized on beads. We compared this EIA and an immunofluorescence (IF) assay in a large group of patients and controls. Methods: We studied 492 healthy individuals and 307 patients with connective tissue diseases (CTDs). Sera were tested by an automated EIA (COBAS® Core HEp2 ANA EIA; Roche Diagnostics) and IF. Samples were also tested for eight disease-specific antibodies, including antibodies against U1RNP, Sm, SSA/Ro, SSB/La, Scl-70, Jo-1, dsDNA, and centromere. Results: Areas under ROC curves for the EIA were greater than (P = 0.008–0.012) or numerically identical to areas for the IF method for each of six CTDs studied. ROC areas for EIA were 0.98 (95% confidence interval, 0.95–0.99), 0.99 (0.96–1.00), and 0.99 (0.98–1.00) in systemic lupus erythematosus (n = 111), systemic sclerosis (n = 39), and mixed connective tissue disease (n = 33), respectively. For all 258 CTD patients with conditions other than rheumatoid arthritis (RA), the sensitivity and specificity of the IF method at a cutoff dilution of 1:40 were 92% and 65%, respectively, vs 93% and 79% for the EIA at a cutoff of 0.6. For the IF method at a cutoff dilution of 1:160, sensitivity and specificity were 81% and 87%, respectively, vs 84% and 94%, respectively, for the EIA at a cutoff of 0.9. For 207 sera containing at least one of eight disease-specific ANAs, positivities for the EIA and the IF method were 97.1% and 97.6%, respectively, at cutoffs of 0.6 and 1:40 (P = 0.76). Conclusions: An EIA that can be performed by a fully automated instrument distinguishes CTDs (except RA) from healthy individuals with both higher sensitivity and specificity than the IF method when the cutoff index was set at 0.9. Moreover, it can be used to exclude the presence of disease-specific ANAs by setting the cutoff index at 0.6 with almost the same efficacy as the IF method.


2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 2040-2040
Author(s):  
Hongmei Tao ◽  
Xing Tang ◽  
Yue Lin ◽  
Chris Chang Yu ◽  
Xuedong Du

2040 Background: While the current cancer screening methods mostly failed to detect cerebral cancer, a novel, promising technology named cancer differentiation analysis (CDA) technology has been developed to measure novel bio-physical properties to obtain valuable multi-level and multi-parameter information including protein, cellular and molecular level information. Initial results showed that CDA technology is capable of detecting cerebral cancer with a high degree of sensitivity and specificity. Methods: In this study, samples from 78 cerebral cancer patients and 321 healthy individuals were measured. Peripheral blood of each individual was drawn in EDTA tubes. One class of bio-physical property in blood samples was utilized for CDA tests. CDA data were conducted using SPSS, and the results were shown in table. Results: The average CDA values of cerebral cancer and control groups were 52.30 and 33.38 (rel. units) respectively. The results indicated that cerebral cancer could be significantly distinguished from the control (p < 0.001). Area under ROC curve (AUC) was 0.980, and sensitivity and specificity was 92.3% and 96.6% respectively. Conclusions: Initial results showed that CDA technology could effectively distinguish cerebral cancer from healthy individuals. As a novel bio-physical based cancer detection approach with multi-level and multi-parameter expressions, CDA could be a potential candidate for cerebral cancer screening. Results from Statistical Analysis of CDA. [Table: see text]


2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Rohit Jain ◽  
Pankaj Aggarwal ◽  
Gajendra Nath Gupta

Introduction. In India, family/replacement donors still provide more than 45% of the collected blood. With increasing voluntary blood donation and the still-prevalent infectious diseases in donors, we need to augment transfusion-transmitted infections (TTIs) testing before use. Our study was aimed to know the seroprevalence of TTIs among the donors of Rajasthan and the need for newer technologies like nucleic acid testing (NAT). Materials and Methods. Enhanced chemiluminescence immunoassay (ECi) was used for detection of HBsAg, anti-HIV, and anti-HCV in donor serum. 50% of the blood units which were negative on ECi were randomly selected and subjected to NAT testing for HBV, HCV, and HIV. Results. The total seroprevalence of TTIs is 2.62%. Of the randomly selected donor units negative by ECi, 8 turned out to be reactive on NAT testing: 4 were voluntary and 4 were family/replacement donors. Combined NAT yield (NAT reactive/seronegative) for HIV, HCV, and HBV was 0.034% (1 in 2972 donations). All the 8 reactive samples were positive for HBV DNA. Conclusion. In countries with a high prevalence of TTIs like India there are likely to be a significant number of window period donations that can be identified by NAT which may be implemented in blood centers allover India with serological testing to provide safe blood and cost alone should not be a deterrent to the government and implementing agencies.


2020 ◽  
Vol 5 (4) ◽  
pp. 1-29
Author(s):  
Farid E. Ahmed ◽  
Mostafa M. Gouda ◽  
Nancy C. Ahmed

Isolation methods that employ readily-available inexpensive supplies on the open market, which are reliable, as well as economical, such as nucleic acid amplification techniques (NAAT) based on microfluidic technology in low-resource research settings (LRRS) that meets the ASSURED guidelines are essential to develop a noninvasive diagnostic colon cancer screen in stool using micro(mi)RNA molecules. A combination of a microfluidic-based MiRNA stool test with a reliable rolling circle amplification/detection method applied to the quantification of miRNA molecules, result in an affordable sensitive and specific isothermal method for the noninvasive quantitative detection of miRNAs in LRRS. Scientists and engineers have become interested in miRNAs, and they have intensified their efforts to apply emerging simple detection tools to the important bioanalytical challenge of quantifying these small 18-26 nt long molecules. Some of the proposed approaches incorporate novel material, such as simple centrifuges and methods based on microfluidic technology, while others utilize the interesting biological properties of these molecules, such as forming branched RCA structures, allowing for the detection of these biomarker molecules at an attomolar "aM" concentration level, using low cost extraction and isothermal amplification methods in LRRS. We have been interested in studying colorectal cancer (CRC) because it is the 3rd most common malignancy worldwide, and stool can be obtained noninvasively from the patients. We have focused in this research on colon cancer (CC) because it is more common in the USA than rectal cancer (RC). The innovation of our approach lies in the exploratory use of an affordable, quantitative miRNA profiling in noninvasive stool samples in LRRS, whose extracted fragile total RNA is stabilized shortly after excretion from stool by commercially available kits, so it does not ever fragment, followed by quantitative standardized analytical tests that are neither labor intensive, nor require expensive instrumentation, in order to develop apanel of novel miRNA genes for the noninvasive diagnostic screening of early left and right sporadic colon cancers, more economically, and with higher sensitivity and specificity than any other colon cancer screening test currently available on the market. To show the clinical sensitivity and specificity of the proposed quantitative miRNA test using simple methodologies in LRRS,the miRNA results are to be correlated with FOBT, colonoscopy, and pathology data. Standardization establishes test’s performance criteria (sample selection, optimal sample running conditions, preservation and storage), in order to ensure that the assay will perform the same way in any laboratory, by any trained personnel, anywhere in low-resource laboratory settings worldwide.


2020 ◽  
Author(s):  
Golam Sarower Bhuyan ◽  
Aftab Uz Zaman Noor ◽  
Rosy Sultana ◽  
Farjana Akther Noor ◽  
Nusrat Sultana ◽  
...  

AbstractTransfusion transmitted infections (TTIs) have remained a major deterrent to public health, particularly among the patients with transfusion-dependent Beta thalassemia in developing countries. Although proper donor selection through adoption of WHO-advised infection panel has lowered the rate of infections, the multi-transfused patients are not free of risk. The present study screened 148 transfusion-dependent Beta thalassemia patients to determine the frequency of HCV, HBV and HIV using ELISA method. Among these patients, infected cases with HCV, HBV and HIV were 13.51%, 3.37% and 0%, respectively. Moreover, 2% of the patients had co-infections with both HBV and HCV. The percentage of infections in the patients with frequent transfusion interval (≤30 days) was significantly higher (P<0.0005) than that in the patients with less frequent transfusion intervals (>30 days). Immunochromatography (ICT)-based rapid test kits are usually used to screen and confirm these infections in the blood of the patients. However, ICT-based tests are not sensitive enough to detect the infections. So, a combination of both Nucleic Acid testing (NAT) and serological testing are suggested to significantly reduce the risk of viral infections during blood transfusion.


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