Development, performance evaluation, and clinical application of a Rapid SARS‐CoV‐2 IgM and IgG Test Kit based on automated fluorescence immunoassay

Abstract

The ongoing COVID‐19 epidemic has made a huge impact on health, economies, and societies all over the world. Although RT‐PCR‐based nucleic acid detection has been primarily used in the diagnosis of COVID‐19, it is time‐consuming with limited application scenarios and must be operated by qualified personnel. Antibody test, particularly point‐of‐care antibody testing, is a suitable complement to nucleic acid test as it provides rapid, portable, and cost‐effective detection of infections. In this study, a rapid antibody test kit was developed based on fluorescence immunochromatography for the sensitive, accurate, and automated detection of IgM and IgG antibodies against SARS‐CoV‐2 in human serum, plasma, and whole blood samples within 10 minutes. The sensitivity, specificity, precision, and stability of the test kit were of good performance. No cross‐activity and no interference was observed. In the multiple‐center parallel study, 223 samples from hospitalized patients were used to evaluate the clinical specificity of the test. Both SARS‐CoV‐2 IgM and IgG achieved a clinical specificity of 98.21%. The clinical sensitivities of SARS‐CoV‐2 IgM and IgG were 79.54% and 87.45%, respectively, among 733 RT‐PCR confirmed SARS‐Cov‐2 samples. For the combined IgM and IgG assays, the sensitivity and specificity were 89.22% and 96.86%, respectively. Our results demonstrate that the combined use of IgM and IgG could serve as a more suitable alternative detection method for COVID‐19 patients, and the developed kit is of great public health significance for the prevention and control of the COVID‐19 pandemic. This article is protected by copyright. All rights reserved.

Serum albumin concentrations are associated with disease severity and outcomes in coronavirus 19 disease (COVID-19): a systematic review and meta-analysis

“…Conversely, we found a relation between effect size and inflammation in accordance with previous studies by Huang et al [ 42 ], which found that albumin concentrations were inversely correlated with WBC, neutrophil-to-lymphocyte ratio (NLR) and CRP, and by Huang et al [ 43 ], that describe an inverse relationship between serum albumin and IL-6. As suggested by Huang et al [ 42 ] hypoalbuminemia might be due to the presence of a systemic inflammatory state in COVID‐19. It is well known that inflammation may be responsible for the extravasation of serum albumin into the interstitial space due to an augmented capillary permeability, with an increased volume distribution of albumin [ 102 ].…”

“…Notably, our analyses did not show any association between effect size and the liver function biomarkers ALT and AST, confirming previous observations that hypoalbuminemia in COVID-19 patients is not related to liver dysfunction [ 42 ]. Conversely, we found a relation between effect size and inflammation in accordance with previous studies by Huang et al [ 42 ], which found that albumin concentrations were inversely correlated with WBC, neutrophil-to-lymphocyte ratio (NLR) and CRP, and by Huang et al [ 43 ], that describe an inverse relationship between serum albumin and IL-6. As suggested by Huang et al [ 42 ] hypoalbuminemia might be due to the presence of a systemic inflammatory state in COVID‐19.…”

“…A total of 19,760 COVID-19 patients were studied, 13,628 (49% males, mean age 53 years) with low severity or favourable outcome and 6141 (58% males, mean age 65 years) with high severity or poor outcome. Three studies were prospective [ 29 , 41 , 52 ], 51 retrospective [ 20 – 28 , 30 – 34 , 36 – 39 , 42 – 46 , 48 – 51 , 53 , 54 , 57 – 60 , 62 , 63 , 65 , 66 , 69 – 76 , 78 , 80 , 81 , 83 – 86 ], while 13 did not specifically declare the study design [ 23 , 35 , 40 , 47 , 55 , 56 , 61 , 64 , 67 , 68 , 77 , 79 , 82 ]. Fifty-two studies (77.6%) were performed in China [ 22 , 24 – 26 , 28 – 31 , 33 – 35 , 37 – 43 , 46 – 57 , 59 , 62 – 64 , 68 – 85 ] while the remaining 15 were conducted in the rest of the world [ 20 , 21 , 23 , 27 , 32 , 36 , 44 ,…”

“…Fifty-two studies (77.6%) were performed in China [ 22 , 24 – 26 , 28 – 31 , 33 – 35 , 37 – 43 , 46 – 57 , 59 , 62 – 64 , 68 – 85 ] while the remaining 15 were conducted in the rest of the world [ 20 , 21 , 23 , 27 , 32 , 36 , 44 , 45 , 58 , 60 , 61 , 65 – 67 , 86 ]. Endpoints included disease severity based on current clinical guidelines (31 studies, 46%) [ 22 , 24 , 28 , 32 , 33 , 35 , 36 , 38 , 39 , 44 – 47 , 49 – 52 , 54 , 56 , 58 , 64 , 66 , 69 , 72 , 73 , 75 , 77 , 79 , 81 – 83 ], survival (19 studies, 28%) [ 20 , 23 , 26 , 30 , 31 , 34 , 42 , 53 , 59 – 62 , 65 , …”

Herz-Kreislauf-Erkrankungen und COVID-19

“…Die pathologischen Veränderungen des adaptiven Immunsystems durch SARS-CoV‑2 verhindern auch eine effiziente Bildung von Gedächtnis-T- und B‑Zellen, die für die Ausbildung der Immunität von COVID-19-Patienten nötig wären – eine Problematik, die durch die sich mehrenden Berichte von Reinfektionen verschärft wird [ 29 , 30 ]. Erfreulicherweise scheint aber doch bei vielen Patienten eine Langzeitimmunität zu bestehen, da Gedächtniszellen gegen COVID-19 bis zu 8 Monate nach Infektionsabheilung nachgewiesen wurden.…”