IgG from patients with mild or severe COVID‑19 reduces the frequency and modulates the function of peripheral mucosal-associated invariant T cells in PBMCs from healthy individuals

Nicolle Rakanidis Machado; Beatriz Oliveira Fagundes; Iara Grigoletto Fernandes; Daniela Terra De Apoena Reche; Maria Notomi Sato; Jefferson Russo Victor

doi:10.3892/br.2023.1677

IgG from patients with mild or severe COVID‑19 reduces the frequency and modulates the function of peripheral mucosal-associated invariant T cells in PBMCs from healthy individuals

Biomed Rep. 2023 Oct 16;19(6):95. doi: 10.3892/br.2023.1677. eCollection 2023 Dec.

Authors

Nicolle Rakanidis Machado¹, Beatriz Oliveira Fagundes¹, Iara Grigoletto Fernandes¹, Daniela Terra De Apoena Reche², Maria Notomi Sato¹, Jefferson Russo Victor^{1

2

3}

Affiliations

¹ Laboratory of Medical Investigation LIM-56, Division of Dermatology, Medical School, University of São Paulo, São Paulo 05403-000, Brazil.
² Post Graduation Program in Health Sciences, Santo Amaro University (UNISA), São Paulo 04829-300, Brazil.
³ Medical School, Santo Amaro University (UNISA), São Paulo 04829-300, Brazil.

Abstract

Lower levels of peripheral mucosal-associated invariant T (MAIT) cells have been observed in the peripheral blood of patients with severe coronavirus disease 2019 (COVID-19). Following on from previous research into the effect of the IgG repertoire on human lymphocytes, the present study aimed to evaluate if immunoglobulin G (IgG) antibodies obtained from patients with mild or severe COVID-19 contribute to these effects on MAIT cells. Culture experiments were performed using healthy human peripheral blood mononuclear cells (PBMCs) and different repertoires of IgG obtained from patients with COVID-19 as a mild or severe disease and compared with mock, healthy control or therapeutic IgG conditions. The results indicate that the IgG repertoire induced during the development of mild and severe COVID-19 has, per se, the in vitro potential to reduce the frequency of MAIT cells and the production of IFN-γ by the MAIT cell population in PBMCs from healthy individuals. In conclusion, the results of the present study indicate that IgG in patients with severe COVID-19 may participate in the reduction of peripheral MAIT cell frequency and hinder the antiviral activity of these cells.

Keywords: COVID-19; IFN-γ; IL-17; IgG; mucosal-associated invariant T cells.

Grants and funding

Funding: The present study was supported by the Laboratory of Medical Investigation-56, Medical School, University of São Paulo, São Paulo, Brazil (LIM-56 HC-FMUSP), the National Council for Scientific and Technological Development (CNPq; grant no. 302937/2021-8) and São Paulo Research Foundation (FAPESP; grant no. 2021/08225-8).