Comparison of Four T-cell Assays and Two Binding Antibody Assays in SARS-CoV-2 Vaccinees With or Without Omicron Breakthrough Infection
10.3343/alm.2023.43.6.596
- Author:
Yeon Ju SEO
1
;
Inseong OH
;
Minjeong NAM
;
Sue SHIN
;
Eun Youn ROH
;
Eun Young SONG
Author Information
1. Department of Laboratory Medicine, Seoul National University Hospital, Seoul, Korea
- Publication Type:Original Article
- From:Annals of Laboratory Medicine
2023;43(6):596-604
- CountryRepublic of Korea
- Language:English
-
Abstract:
Background:Several T-cell response assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are available; however, their comparability and correlations with antibody responses remain unclear. We compared four SARS-CoV-2 T-cell response assays and two anti-SARS-CoV-2 spike antibody assays.
Methods:We enrolled 89 participants who had received a booster dose of the BNT162b2 vaccine after two doses of the ChAdOx1 or BNT162b2 vaccine. Fifty-six participants without breakthrough infection (BI) (ChAdOx1/BNT162b2 group: N=27; BNT162b2 group: N=29) and 33 with BI were included. We evaluated two whole-blood interferon-gamma release assays (IGRAs) (QuantiFERON and Euroimmun), T-SPOT.COVID, an in-house enzyme-linked immunospot (ELISPOT) assay (targeting the spike and nucleocapsid peptides of wild-type and Omicron SARS-CoV-2), Abbott IgG II Quant, and Elecsys Anti-S, using Mann–Whitney U, Wilcoxon signed-rank, and Spearman’s correlation tests.
Results:The correlations between the IGRAs and between the ELISPOT assays (ρ=0.60–0.70) were stronger than those between the IGRAs and ELISPOT assays (ρ=0.33–0.57). T-SPOT.COVID showed a strong correlation with Omicron ELISPOT (ρ=0.70). The anti-spike antibody assays showed moderate correlations with T-SPOT.COVID, Euroimmun IGRA, and ELISPOT (ρ=0.43–0.62). Correlations tended to be higher in the BI than in the noninfected group, indicating that infection induces a stronger immune response.
Conclusions:T-cell response assays show moderate to strong correlations, particularly when using the same platform. T-SPOT.COVID exhibits potential for estimating immune responses to the Omicron variant. To accurately define SARS-CoV-2 immune status, both T-cell and B-cell response measurements are necessary.
