Generation of Cytotoxic T cells and Dysfunctional CD8 T Cells in Severe COVID19 Patients

COVID-19, the infectious disease caused by SARS-CoV-2, has spread on a pandemic scale. The virus infection can evolve asymptomatically or generate severe symptoms, influenced by the presence of comorbidities. Lymphopenia in patients affected with COVID-19 according to the severity of symptoms is frequent. However, the profile of CD4+ and CD8+ T-cells regarding cytotoxicity and antiviral factor expression has not yet been completely elucidated in acute SARS-CoV-2 infections. The purpose of this study is to evaluate the phenotypic and functional profile of T-lymphocytes in patients with moderate and severe/critical COVID-19. During this pandemic period, we analyzed a cohort of 62 confirmed patients with SARS-CoV-2 (22 moderate cases and 40 severe/critical cases). Albeit lymphopenia, we observed an increase in the expression of CD28, co-stimulator molecule, and activation markers (CD38 and HLA-DR) in T-lymphocytes as well as an increase in the frequency of CD4+ T-cells, CD8+ T-cells, and NK cells that express the immunological checkpoint protein, PD-1, in patients with severe/critical condition compared to healthy controls. Regarding the cytotoxic profile of peripheral blood mononuclear cells, an increase in the response of CD4+ T-cells already at baseline level was observed, scarcely changed upon PMA and Ionomycin stimulation. Meanwhile, CD8+ T-lymphocytes decreased cytotoxic response, evidencing a profile of exhaustion in patients with severe COVID-19. As observed in the t-SNE technique CD4+ T-cytotoxic and CD8+ T with low granzyme production evidencing their dysfunctionality in severe/critical conditions. In addition, purified CD8+ T-lymphocytes from patients with severe COVID-19 showed an increased constitutive expression of differentially expressed genes associated with the caspase pathway, inflammasome, and antiviral factors, and curiously, reduced expression of TNF-α. The cytotoxic profile, by CD4+ T-cells, may compensate for the dysfunction/exhaustion of TCD8+ in acute SARS-CoV-2 infection. These findings may provide an understanding of the interplay of cytotoxicity between CD4+ T-cells and CD8+ T-cells in the severity of acute COVID-19 infection..

Medienart:

Preprint

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Preprints.org - (2022) vom: 31. Okt. Zur Gesamtaufnahme - year:2022

Sprache:

Englisch

Beteiligte Personen:

Gozzi-Silva, Sarah Cristina [VerfasserIn]
Oliveira, Luana de Mendonça [VerfasserIn]
Alberca, Ricardo Wesley [VerfasserIn]
Pereira, Nátalli Zanete [VerfasserIn]
Yoshikawa, Fabio Seiti [VerfasserIn]
Pietrobon, Anna Julia [VerfasserIn]
Yendo, Tatiana Mina [VerfasserIn]
Andrade, Milena Mary [VerfasserIn]
Ramos, Yasmim Álefe Leuzzi [VerfasserIn]
Brito, Cyro Alves [VerfasserIn]
Oliveira, Emily Araújo [VerfasserIn]
Beserra, Danielle Rosa [VerfasserIn]
Duarte, Alberto José da Silva [VerfasserIn]
Sato, Maria Notomi [VerfasserIn]

Links:

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Themen:

570
Biology

doi:

10.20944/preprints202208.0496.v1

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

preprintsorg037086235