Combined assessment of S- and N-specific IL-2 and IL-13 secretion and CD69 neo-expression for discrimination of post-infection and post-vaccination cellular SARS-CoV-2-specific immune response.

Abstract

BACKGROUND:

Antibody-based tests are available for measuring SARS-CoV-2-specific immune responses but fast T-cell assays remain scarce. Robust T cell-based tests are needed to differentiate specific cellular immune responses after infection from those after vaccination.

METHODS:

One hundred seventeen individuals (COVID-19 convalescent patients: n = 40; SARS-CoV-2 vaccinees: n = 41; healthy controls: n = 36) were evaluated for SARS-CoV-2-specific cellular immune responses (proliferation, Th1, Th2, Th17, and inflammatory cytokines, activation-induced marker [AIM] expression) by incubating purified peripheral blood mononuclear cells (PBMC) or whole blood (WB) with SARS-CoV-2 peptides (S, N, or M), vaccine antigens (tetanus toxoid, tick borne encephalitis virus) or polyclonal stimuli (Staphylococcal enterotoxin, phytohemagglutinin).

RESULTS:

N-peptide mix stimulation of WB identified the combination of IL-2 and IL-13 secretion as superior to IFN-γ secretion to discriminate between COVID-19-convalescent patients and healthy controls (p < .0001). Comparable results were obtained with M- or S-peptides, the latter almost comparably recalled IL-2, IFN-γ, and IL-13 responses in WB of vaccinees. Analysis 10 months as opposed to 10 weeks after COVID-19, but not allergic disease status, positively correlated with IL-13 recall responses. WB cytokine responses correlated with cytokine and proliferation responses of PBMC. Antigen-induced neo-expression of the C-type lectin CD69 on CD4+ (p < .0001) and CD8+ (p = .0002) T cells informed best about the SARS-CoV-2 exposure status with additional benefit coming from CD25 upregulation.

CONCLUSION:

Along with N- and S-peptide-induced IL-2 and CD69 neo-expression, we suggest to include the type 2 cytokine IL-13 as T-cellular recall marker for SARS-CoV-2 specific T-cellular immune responses after infection and vaccination.

• Authors: Bernhard Kratzer, Larissa C Schlax, Pia Gattinger, Petra Waidhofer-Söllner, Doris Trapin, Peter A Tauber, Al Nasar Ahmed Sehgal, Ulrike Körmöczi, Arno Rottal, Melanie Feichter, Teresa Oberhofer, Katharina Grabmeier-Pfistershammer, Kristina Borochova, Yulia Dorofeeva, Inna Tulaeva, Milena Weber, Bernhard Mühl, Anna Kropfmüller, Bettina Negrin, Michael Kundi, Rudolf Valenta, Winfried F Pickl
• Journal: Allergy (Allergy) Vol. 77 Issue 11 Pg. 3408-3425 (11 2022) ISSN: 1398-9995 [Electronic] Denmark
• PMID: 35690994 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2022 The Authors. Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.

Chemical References

• Cytokines
• Interleukin-13
• Interleukin-2
• CD69 antigen

Topics

• Humans
• COVID-19
• Cytokines (metabolism)
• Immunity, Cellular
• Interleukin-13
• Interleukin-2
• Leukocytes, Mononuclear (metabolism)
• SARS-CoV-2
• Vaccination