Author Correction: Performance and usefulness of a novel automated immunoassay HISCL SARS-CoV-2 Antigen assay kit for the diagnosis of COVID-19

AbstractHere, we aimed to evaluate the clinical performance of a novel automated immunoassay HISCL SARS-CoV-2 Antigen assay kit designed to detect the nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This kit comprises automated chemiluminescence detection systems. Western blot analysis confirmed that anti-SARS-CoV antibodies detected SARS-CoV-2N proteins. The best cut-off index was determined, and clinical performance was tested using 115 serum samples obtained from 46 patients with coronavirus disease 2019 (COVID-19) and 69 individuals who tested negative for COVID-19 through reverse transcription quantitative polymerase chain reaction (RT-qPCR). The HISCL Antigen assay kit showed a sensitivity of 95.4% and 16.6% in samples with copy numbers > 100 and < 99, respectively. The kit did not cross-react with human coronaviruses causing seasonal common cold and influenza, and none of the 69 individuals without COVID-19 were diagnosed with positive results. Importantly, 81.8% of the samples with low virus load (< 50 copy numbers) were diagnosed as negative. Thus, using HISCL antigen assay kits may reduce overdiagnosis compared with RT-qPCR tests. The rapid and high-throughput HISCL SARS-CoV-2 Antigen assay kit developed here proved suitable for screening infectious COVID-19 and may help control the pandemic.

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Performance and Usefulness of a Novel Automated Immunoassay HISCL SARS-CoV-2 Antigen Assay Kit for the Diagnosis of COVID-19

10.21203/rs.3.rs-460544/v1 ◽

2021 ◽

Author(s):

Kaori Saito ◽

Tomohiko Ai ◽

Akinori Kawai ◽

Jun Matsui ◽

Yoshiyuki Fukushima ◽

...

Keyword(s):

Clinical Performance ◽

Quantitative Polymerase Chain Reaction ◽

Serum Samples ◽

N Protein ◽

Detection Systems ◽

Copy Numbers ◽

Antigen Assay ◽

Polymerase Chain ◽

Automated Immunoassay ◽

Corona Viruses

Abstract Background: The aim of this study was to evaluate the clinical performance of a newly developed automated immunoassay HISCL SARS-CoV-2 Antigen assay kit designed to detect the nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods: The HISCL SARS-CoV-2 Antigen assay kit is composed of automated chemiluminescence detection systems. Western blot analysis confirmed that anti-SARS-CoV antibodies detected SARS-CoV-2 N proteins. The best cut-off index (COI) was determined using human serum samples obtained from coronavirus disease-2019 (COVID-19) patients and patients without COVID-19. To test the clinical performance, 115 samples obtained from 46 patients with COVID-19 and 69 individuals who tested negative for COD-19 using reverse transcription quantitative polymerase chain reaction (RT-qPCR) were used. Results: The HISCL antigen assay kit showed a sensitivity of 95.4 % in the samples with copy numbers of >100, and a sensitivity of 16.6 % in the samples with copy numbers of <99. The kit did not cross-react with other human corona viruses causing seasonal common cold (HCoV 229E, OC43, NL63, and HKU1) and influenza (H1N1, H3N2, and B), and none of the 69 individuals with negative RT-qPCR results were diagnosed as positive. Importantly, 81.8 % of the samples with low virus load (<50 copy numbers) were diagnosed as negative. Thus, use of the HISCL antigen assay kit may reduce overdiagnosis compared with RT-qPCR tests. Conclusion: The rapid and high-throughput HISCL SARS-CoV-2 Antigen assay kit developed in this study can be used as a suitable screening test for infectious COVID-19, and may play a role in controlling the pandemic.

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Diagnostik der Hepatitis C Virus Infektion: Rolle des HCV-Core Antigen Assay

Zeitschrift für Gastroenterologie ◽

10.1055/s-0035-1555413 ◽

2015 ◽

Vol 41 (08) ◽

Author(s):

HL Tillmann ◽

J Wiegand ◽

I Glomb ◽

A Jelineck ◽

G Picchio ◽

...

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Core Antigen ◽

Hcv Core Antigen ◽

Antigen Assay

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Relationship Between Total Prothrombin, Native Prothrombin and the International Normalized Ratio (INR)

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656342 ◽

1992 ◽

Vol 68 (02) ◽

pp. 160-164 ◽

Cited By ~ 3

Author(s):

P J Braun ◽

K M Szewczyk

Keyword(s):

Anticoagulant Therapy ◽

Oral Anticoagulant ◽

Inverse Relationship ◽

Low Dose ◽

Oral Anticoagulant Therapy ◽

International Normalized Ratio ◽

Antigen Assay ◽

Dose Oral ◽

Anticoagulated Patients ◽

Sensitive Method

SummaryPlasma levels of total prothrombin and fully-carboxylated (native) prothrombin were compared with results of prothrombin time (PT) assays for patients undergoing oral anticoagulant therapy. Mean concentrations of total and native prothrombin in non-anticoagulated patients were 119 ± 13 µg/ml and 118 ± 22 µg/ml, respectively. In anticoagulated patients, INR values ranged as high as 9, and levels of total prothrombin and native prothrombin decreased with increasing INR to minimum values of 40 µg/ml and 5 µg/ml, respectively. Des-carboxy-prothrombin increased with INR, to a maximum of 60 µg/ml. The strongest correlation was observed between native prothrombin and the reciprocal of the INR (1/INR) (r = 0.89, slope = 122 µg/ml, n = 200). These results indicated that native prothrombin varied over a wider range and was more closely related to INR values than either total or des-carboxy-prothrombin. Levels of native prothrombin were decreased 2-fold from normal levels at INR = 2, indicating that the native prothrombin antigen assay may be a sensitive method for monitoring low-dose oral anticoagulant therapy. The inverse relationship between concentration of native prothrombin and INR may help in identification of appropriate therapeutic ranges for oral anticoagulant therapy.

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A Comparison of Methods for the Measurement of Activated Factor VII

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656369 ◽

1992 ◽

Vol 68 (03) ◽

pp. 301-305 ◽

Cited By ~ 24

Author(s):

S Kitchen ◽

R G Malia ◽

F E Preston

Keyword(s):

Factor Viia ◽

Epidemiological Studies ◽

Factor Vii ◽

Haemophilia A ◽

Reference Ranges ◽

Activated Factor Vii ◽

Normal Individuals ◽

Antigen Assay ◽

Activity State ◽

Almost All

SummaryA number of different methods are available for the measurement of factor VIIa. Almost all of these employ ratios of two different measurements of factor VII. In order to determine which is the most sensitive to activated factor VII we have compared currently available methods in the following groups: two patients with haemophilia A following treatment with activated recombinant factor VII (rVII a); 6 normal plasmas during cold promoted activation of factor VII; normal individuals (n = 23); and patients with unequivocal disseminated intravascular coagulation (DIC, n = 19). Factor VII was measured in an amidolytic assay (VII: Amid) and an antigen assay (VII:Ag). Clotting activity was measured using rabbit (VII:C Rab), human (VII:C Hum) and bovine (VII:C Bov) thromboplastin.Of the clotting assays the most sensitive to the presence of factor VIIa was that which utilised bovine thromboplastin. Amidolytic and immunological measurements were unaffected by the activity state of factor VII. The ratios VII:C Rab/VII: Ag and VII:C Rab/VII:Amid were insensitive to activated factor VII. The ratios most sensitive to the presence of factor VII a were VII:C Bov/VII: Amid and VII: C Bov/VII:Ag. The ratios VII:C Bov/VII:C Rab and VII:C Bov/VII:C Hum are less sensitive but have the advantage for epidemiological studies of narrower reference ranges.

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