T Cell Senescence by Extensive Phenotyping: An Emerging Feature of COVID-19 Severity

Jenny Zuin; Paola Fogar; Giulia Musso; Andrea Padoan; Elisa Piva; Michela Pelloso; Francesca Tosato; Annamaria Cattelan; Daniela Basso; Mario Plebani

doi:10.1093/labmed/lmac048

T Cell Senescence by Extensive Phenotyping: An Emerging Feature of COVID-19 Severity

Lab Med. 2022 Nov 3;53(6):609-613. doi: 10.1093/labmed/lmac048.

Authors

Jenny Zuin¹, Paola Fogar¹, Giulia Musso^{1

2}, Andrea Padoan^{1

2}, Elisa Piva¹, Michela Pelloso¹, Francesca Tosato¹, Annamaria Cattelan³, Daniela Basso^{1

2}, Mario Plebani^{1

2}

Affiliations

¹ Department of Laboratory Medicine, Padova University-Hospital, Padova, Italy.
² Department of Medicine-DIMED, University of Padova, Padova, Italy.
³ Unit of Infectious and Tropical Diseases, Padova University-Hospital, Padova, Italy.

Abstract

Objective: To identify the potential prognostic value of lymphocyte subsets in COVID-19 patients, where lymphopenia is a common finding.

Methods: In 353 COVID-19 inpatients and 40 controls T cell subsets with markers of senescence and exhaustion were studied by flow cytometry.

Results: In severe illness, total lymphocytes B, NK, and all T subsets were dampened. Senescent CD4+, but mainly CD8+ T cells, increased in patients with respect to controls. The most significant index predicting fatal outcome was neutrophils/CD3+ T ratio.

Conclusion: In conclusion, an altered T cell pattern underlies COVID-19 severity and is involved in predicting the outcome.

Keywords: COVID-19; T cell subsets; exhaustion; extensive immunophenotyping; prognostic biomarker; senescence.

MeSH terms

CD8-Positive T-Lymphocytes
COVID-19*
Cellular Senescence
Humans
Lymphocyte Subsets
T-Lymphocyte Subsets