Co-expression of Foxp3 and Helios facilitates the identification of human T regulatory cells in health and disease

Lyra Morina; Madalyn E Jones; Cihan Oguz; Mariana J Kaplan; Arunakumar Gangaplara; Courtney D Fitzhugh; Christopher G Kanakry; Ethan M Shevach; Maja Buszko

doi:10.3389/fimmu.2023.1114780

Co-expression of Foxp3 and Helios facilitates the identification of human T regulatory cells in health and disease

Front Immunol. 2023 Jun 7:14:1114780. doi: 10.3389/fimmu.2023.1114780. eCollection 2023.

Authors

Lyra Morina¹, Madalyn E Jones¹, Cihan Oguz^{2

3}, Mariana J Kaplan⁴, Arunakumar Gangaplara⁵, Courtney D Fitzhugh⁵, Christopher G Kanakry⁶, Ethan M Shevach¹, Maja Buszko¹

Affiliations

¹ Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States.
² NIAID Collaborative Bioinformatics Resource, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States.
³ Axle Informatics, Bethesda, MD, United States.
⁴ Systemic Autoimmunity Branch, National Institute of Arthritis, Musculoskeletal and Skin Diseases, Bethesda, MD, United States.
⁵ Laboratory of Early Sickle Mortality, National Heart, Lung and Blood Institute, Bethesda, MD, United States.
⁶ Center for Immuno-Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States.

Abstract

Foxp3 is regarded as the major transcription factor for T regulatory (T_reg) cells and expression of Foxp3 is used to identify and quantitate Treg cells in mouse models. However, several studies have demonstrated that human CD4⁺ T conventional (T_conv) cells activated in vitro by T cell receptor (TCR) stimulation can express Foxp3. This observation has raised doubt as to the suitability of Foxp3 as a T_reg marker in man. Helios, a member of the Ikaros gene family, has been shown to be expressed by 80-90% of human Foxp3⁺ T_reg cells and can potentially serve as a marker of human T_reg. Here, we confirm that Foxp3 expression is readily upregulated by T_conv upon TCR stimulation in vitro, while Helios expression is not altered. More importantly, we show that Foxp3 expression is not elevated by stimulation of hT_conv in a humanized mouse model of graft versus host disease (GVHD) and in patients with a wide variety of acute and chronic inflammatory diseases including sickle cell disease, acute and chronic GVHD, systemic lupus erythematosus, as well as critical COVID-19. In all patients studied, an excellent correlation was observed between the percentage of CD4⁺ T cells expressing Foxp3 and the percentage expressing Helios. Taken together, these studies demonstrate that Foxp3 is not induced upon T_conv cell activation in vivo and that Foxp3 expression alone can be used to quantitate T_reg cells in humans. Nevertheless, the combined use of Foxp3 and Helios expression provides a more reliable approach for the characterization of T_reg in humans.

Keywords: Foxp3; GVHD; Helios; SLE; SLe; regulatory T cell.

Publication types

Research Support, N.I.H., Intramural

MeSH terms

Animals
COVID-19* / metabolism
Forkhead Transcription Factors / genetics
Forkhead Transcription Factors / metabolism
Graft vs Host Disease* / metabolism
Humans
Mice
Receptors, Antigen, T-Cell / metabolism
T-Lymphocytes, Regulatory / metabolism
Transcription Factors / metabolism

Substances

Transcription Factors
Receptors, Antigen, T-Cell
Foxp3 protein, mouse
Forkhead Transcription Factors

Grants and funding

These studies were supported by the Divisions of Intramural Research of the National Institute of Allergy and Infectious Diseases, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Heart, Lung, and Blood Institute, and the National Cancer Institute.