Lab Med Online.  2018 Oct;8(4):140-147. 10.3343/lmo.2018.8.4.140.

Clinical Usefulness of ImmuneCheckâ„¢ IgG for Rapid Semiquantitation of Total IgG

• Choi J
• Lee SC
• Park KH
• Yoon H
• Kim HS
• Park JW

• KMID: 2421004
• DOI: http://doi.org/10.3343/lmo.2018.8.4.140

Abstract

BACKGROUND
Conventional IgG assays require costly equipment and skilled experts. Semiquantitative measurement of total IgG using point-of-care testing devices may be the solution for these limitations. This study evaluated the reproducibility of the ImmuneCheckâ„¢ IgG assay (ProteomeTech Inc., Korea) and the correlation of its results with conventional laboratory IgG results in the serum and whole blood.
METHODS
Both the serum and whole blood samples from 120 patients were used. To evaluate the intra-test reproducibility and inter-test correlation, intraclass correlation coefficient (ICC) analysis was used.
RESULTS
The concentration of serum total IgG measured by cobas® 6000 (Roche Diagnostics, Switzland) ranged from 690.4 to 2,756.4 mg/dL. The intra-test reproducibility of ImmuneCheckâ„¢ IgG was high (Serum ICC=0.724, P < 0.001; Whole blood ICC=0.843, P < 0.001). The inter-test correlation between the ImmuneCheckâ„¢ IgG and cobas® 6000 results was very good (Serum ICC=0.805, P < 0.001; Whole blood ICC=0.842, P < 0.001). Because there were no samples with a total IgG level lower than 600 mg/dL, the pre-existing serum samples were diluted and then the linearity tests were conducted. The intra-test reproducibility for the diluted serum samples was almost perfect (ICC=0.995, P < 0.001), and the inter-test correlation between the ImmuneCheckâ„¢ IgG and cobas® 6000 results was also strong (ICC=0.992, P < 0.001).
CONCLUSIONS
The ImmuneCheckâ„¢ IgG assay is reproducible and highly correlated with the conventional IgG assay for the serum and whole blood. It could be applied for the rapid detection of total IgG.

Keyword

Total IgG POCT; Rapid semiquantitation; Total IgG assay

MeSH Terms

Humans
Immunoglobulin G*
Point-of-Care Testing
Immunoglobulin G

Figure

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  Fig. 1. Experimental process of ImmuneCheck™ IgG.

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  Fig. 2. Flowchart of ImmuneCheck™ IgG analysis. Fig. 2. Flowchart of ImmuneCheck™ IgG analysis.

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  Fig. 3. Scatter plots of whole blood total IgG titers (A) and serum total IgG titers (B) obtained with ImmuneCheck™ IgG.

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  Fig. 4. Scatter plot of diluted serum total IgG titers obtained with Im-muneCheck™ IgG.

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